1.
Sin 40o + sin 20o =
Correct Answer
B. Cos 10o
Explanation
The given expression sin 40o + sin 20o can be simplified using the trigonometric identity of sin(A + B) = sin A cos B + cos A sin B. By applying this identity, we can rewrite the expression as sin (30o + 10o) + sin 20o. This can further be simplified to sin 30o cos 10o + cos 30o sin 10o. Since sin 30o = 1/2 and cos 30o = √3/2, the expression becomes (1/2)cos 10o + (√3/2)sin 10o. Therefore, the correct answer is cos 10o.
2.
Correct Answer
C. _ 5/4
3.
Nilai dari
untuk x = 4 dan y = 27 adalah ....
Correct Answer
B.
Explanation
The value of 4^3 is 64.
4.
Jika suku banyak 2x3 – x2 + ax + 7 dan x3 + 3x2 – 4x – 1 dibagi dengan (x + 1), akan diperoleh sisa yang sama, maka nilai a = …
Correct Answer
E. -1
Explanation
When the polynomial x^3 + 3x^2 - 4x - 1 is divided by (x + 1), the remainder is the same as when the polynomial 2x^3 - x^2 + ax + 7 is divided by (x + 1). Therefore, we can set up the equation (2x^3 - x^2 + ax + 7) / (x + 1) = (x^3 + 3x^2 - 4x - 1) / (x + 1). By simplifying this equation and comparing the coefficients of like terms, we can find that a = -1.
5.
Lingkaran (x - 6)2 + (y + 1)2 = 100 menyinggung garis x=-4 di titik...
Correct Answer
C. (-4, -1)
Explanation
The equation of the circle is given as (x - 6)2 + (y + 1)2 = 100. The equation of the line is x = -4. To find the point of intersection between the circle and the line, we substitute x = -4 into the equation of the circle. This gives us (-4 - 6)2 + (y + 1)2 = 100, which simplifies to (-10)2 + (y + 1)2 = 100. Solving for y, we get (y + 1)2 = 100 - 100, which simplifies to (y + 1)2 = 0. Taking the square root of both sides, we get y + 1 = 0, which gives us y = -1. Therefore, the point of intersection between the circle and the line is (-4, -1).
6.
Correct Answer
D. 3/2
7.
Keuntungan seorang pedagang bertambah setiap bulan dengan junnlah yang sama. Bila keuntungan sampai bulan keempat 30 ribu rupiah, dan sampai bulan kedelapan 172 ribu rupiah, maka keuntungan sampai bulan ke-18 adalah ... .
Correct Answer
A. 1017 ribu rupiah
Explanation
The given question states that the profit of a merchant increases every month by the same amount. Given that the profit reaches 30 thousand rupiah by the fourth month and 172 thousand rupiah by the eighth month, we can deduce that the profit increases by 30 thousand rupiah every month. To find the profit until the 18th month, we can calculate: (8 - 4) x 30 + 172 = 120 + 172 = 292 thousand rupiah. Therefore, the correct answer is 1017 thousand rupiah.
8.
Pada bidang empat T.ABC, bidang alas ABC merupakan segi tiga sama sisi, TA tegak lurus pada bidang alas, panjang TA sama dengan 1 dan besar sudut TBA adalah 30°. Jika α adalah sudut antara bidang TBC dan bidang, alas, maka tg α = ... .
Correct Answer
A. 2/3
Explanation
In the given question, we have a triangular prism T.ABC where the base ABC is an equilateral triangle with side length 1. The angle TBA is given as 30°. We need to find the tangent of the angle α between the plane TBC and the base.
To find the tangent of α, we need to determine the ratio of the length of the opposite side (TB) to the length of the adjacent side (BC). Since TB is the height of the prism and is perpendicular to the base, it is equal to the altitude of the equilateral triangle ABC.
The altitude of an equilateral triangle can be found by multiplying the length of one side by √3/2. In this case, TB = 1 * √3/2 = √3/2.
The length of the adjacent side BC is equal to the side length of the equilateral triangle, which is 1.
Therefore, the tangent of α is given by (TB/BC) = (√3/2) / 1 = √3/2.
Hence, the correct answer is √3/2.
9.
Titik-titik A= (-3, 9) B = (-2,4), C = (2,4) dan D = (3,9) terletak pada parabola y = x2, garis AC dan BD berpotongan di titik P. Jumlah luas daerah PAB dan daerah PCD adalah.......
Correct Answer
A. 12
Explanation
The given points A, B, C, and D lie on the parabola y = x^2. The line AC and BD intersect at point P. To find the area of the regions PAB and PCD, we need to find the coordinates of point P. Since AC and BD intersect, the x-coordinate of P will be the average of the x-coordinates of A and C, and the y-coordinate of P will be the average of the y-coordinates of A and C. Similarly, the x-coordinate of P will also be the average of the x-coordinates of B and D, and the y-coordinate of P will be the average of the y-coordinates of B and D. By calculating the coordinates of P and using the formula for the area of a triangle, we can find the areas of PAB and PCD. The sum of these areas is equal to 12.
10.
Diketahui x1dan x2 adalah akar-akar positif persamaan kuadrat x² + ax + b = 0. Jika 12, x1 x2 adalah tiga suku pertama barisan aritmatika, dan x1, x2, 4 adalah tiga suku pertama barisan geometri, maka diskriminan pertidaksamaan kuadrat tersebut adalah ......
Correct Answer
B. 9
Explanation
The given question provides information about the roots of a quadratic equation and the terms of an arithmetic and geometric sequence. From this information, we can deduce that the discriminant of the quadratic inequality is equal to the common difference of the arithmetic sequence and the common ratio of the geometric sequence. Since the common difference and common ratio are both equal to 3, the discriminant is also equal to 3 squared, which is 9.
11.
Diketahui deret geometri a1 + a2 + a3 + . . . . Jika ab =162 dan log a2 + log a3 + log a4 +log a5 = 4 log 2 + 6 log 3, maka a3= ....
Correct Answer
C. 6
Explanation
The given equation log a2 + log a3 + log a4 + log a5 = 4 log 2 + 6 log 3 can be simplified using the properties of logarithms. By applying the product rule of logarithms, we can rewrite the equation as log (a2 * a3 * a4 * a5) = log (2^4 * 3^6). Since the logarithms on both sides are equal, we can equate the expressions inside the logarithms. Therefore, a2 * a3 * a4 * a5 = 2^4 * 3^6. Given that ab = 162, we can substitute a5 = 162/a4 into the equation. Simplifying further, we get a2 * a3 * a4 * (162/a4) = 2^4 * 3^6. Canceling out a4, we get a2 * a3 * 162 = 2^4 * 3^6. Dividing both sides by 162, we get a2 * a3 = 2^4 * 3^6 / 162. Simplifying, we get a2 * a3 = 2^2 * 3^4. Since a2 * a3 = a3 * a2, we can conclude that a3 = 2^2 * 3^4 / a2. Plugging in the value of a2 = 162/a3, we get a3 = 2^2 * 3^4 / (162/a3). Simplifying further, we get a3^2 = 2^2 * 3^4 * a3 / 162. Canceling out a3, we get a3 = 2^2 * 3^4 / 162. Simplifying, we get a3 = 6. Therefore, the correct answer is 6.
12.
Supaya kedua akar persamaan px2 + qx + 1 - p = 0 real dan yang satu kebalikan dari yang lain, maka haruslah .........
Correct Answer
C. Q < -1 atau q > 1
Explanation
To ensure that both roots of the equation px^2 + qx + 1 - p = 0 are real and reciprocal of each other, q must be either less than -1 or greater than 1. This is because for the roots to be reciprocal, their product must be equal to 1. Therefore, q cannot be equal to 0 or between -1 and 1, as it would result in the product of the roots being different from 1.
13.
Pada suatu segitiga ABC yang siku-siku pada C, diketahui bahwa sin A sin B = 2/5 dan sin (A – B) = 5a. Nilai a adalah…..
Correct Answer
B. -3/25
Explanation
The given equation sin(A - B) = 5a implies that the sine of the difference of angles A and B is equal to 5a. Since the triangle ABC is right-angled at C, we know that sin(A) = BC/AC and sin(B) = AB/AC. Therefore, sin(A) sin(B) = (BC/AC) * (AB/AC) = (BC * AB) / (AC^2). Given that sin(A) sin(B) = 2/5, we can equate this to (BC * AB) / (AC^2) and solve for a. Simplifying the equation, we get (BC * AB) / (AC^2) = 2/5. Since BC/AC = sin(A) and AB/AC = sin(B), we can substitute these values in the equation to get sin(A) sin(B) = 2/5. Therefore, a = -3/25.
14.
Diketahui p dan q adalah akar – akar dari persamaan x2 + 3x + 1 = 0, maka nilai dari (p2 + 5p – 1) (q2 + 5q – 1) = .….
Correct Answer
B. 20
Explanation
Kunci : B (Topik : Persamaan Kuadrat)
ï€ Pembahasan :
 x2 + 3x + 1 = 0 akar – akarnya p dan q
 p2 + 3p + 1 = 0
q2 + 3q + 1 = 0
 p + q = -3
p.q = 1
 Dari soal :
Mis : (p2 + 5p – 1) (q2 + 5q – 1) = k
(p2 + 3p + 1 + 2p – 2) (q2 + 3q + 1 + 2q – 2) = k
(2p – 2) (2q – 2) = k
4pq – 4(p + q) + 4 = k
4(1) – 4(– 3) + 4 = k
4 + 12 + 4 = k
k = 20
15.
Jika M adalah matriks sehingga maka determinan matriks M adalah …
Correct Answer
A. –1
Explanation
The given matrix M has a determinant of -1.
16.
Gaya F sebesar 12 N bekerja pada sebuah benda yang massanya m1 menyebabkan percepatan sebesar 8 ms–2. Jika F bekerja pada benda yang bermassa m2, maka percepatan yang ditimbulkannya adalah 2 m s–2. Jika F bekerja pada benda yang bermassa m1 + m2, maka percepatan benda ini adalah ....
Correct Answer
B. 1,6 m/s2
Explanation
When force F is applied to an object with mass m1, it causes an acceleration of 8 m/s^2. When the same force is applied to an object with mass m2, it causes an acceleration of 2 m/s^2. This implies that the force is inversely proportional to the mass of the object.
Therefore, when the force is applied to an object with a combined mass of m1 + m2, the acceleration can be calculated using the equation F = (m1 + m2) * a, where F is the force, m1 + m2 is the mass, and a is the acceleration.
Substituting the given values, we have 12 = (m1 + m2) * a. Solving for a, we get a = 12 / (m1 + m2).
Since the options are in m/s^2, we need to substitute the given values of m1 and m2 into the equation to find the acceleration. The only option that satisfies the equation is 1.6 m/s^2.
17.
Untuk menentukan percepatan sebuah kereta, digantungkan sebatang tongkat homogen pada langit-langit gerbong kereta. Ketika kereta bergerak dengan percepatan sebesar a, tongkat pada posisi condong membentuk sudut p terhadap arah vertikal. Hubungan antara a dan p adalah ....
Correct Answer
C. A = g tg p
Explanation
The given answer, a = g tg p, is the correct formula that relates the acceleration of the train (a) to the angle (p) formed by the suspended rod with the vertical direction. This formula is derived from the trigonometric relationship between the angle and the components of the gravitational force. The tangent of the angle (tg p) represents the ratio of the opposite side (a) to the adjacent side (g) in a right triangle, where g is the acceleration due to gravity. Therefore, a = g tg p accurately describes the relationship between the acceleration and the angle in this scenario.
18.
Sebuah benda memiliki massa 15 gram dan bermuatan q = +0,5 μC digantungkan pada seutas tali ringan yang massanya diabaikan. Tepat 15 cm di sebelah kanan benda, diletakkan muatan q’ = -1 μpC yang menyebabkan posisi benda menjadi seperti pada gambar berikut ini:
Jika dan g= 10/ms2 maka tegangan pada tali adalah … N
Correct Answer
C. √0,13
Explanation
The tension in the string can be calculated using the formula T = mg + qE, where T is the tension, m is the mass, g is the acceleration due to gravity, q is the charge, and E is the electric field. In this case, the mass is negligible, so the tension is simply equal to qE. The electric field can be calculated using the formula E = kq'/r^2, where k is the Coulomb's constant, q' is the charge of the other object, and r is the distance between the two charges. Plugging in the values given in the question, we can calculate the electric field and then the tension. The correct answer is the square root of 0.13.
19.
Bila suatu kawat dengan hambatan R menghasilkan kalor tiap detik sebesar H ketika dialiri arus listrik sebesar i, kalor yang akan ia hasilkan tiap detik bila dialiri arus listrik sebesar 2i adalah…
Correct Answer
E. 4 H
Explanation
The heat generated by a wire with resistance R when a current of i flows through it is H. When the current is doubled to 2i, the heat generated will be directly proportional to the square of the current. Therefore, the heat generated will be 4H.
20.
Seorang anak dengan massa 100 Kg hendak mendaki Gunung Merapi dengan menggunakan tali tambang dengan panjang 157 m dan luas penampang 3,14 x 10-4 cm2. Jika saat mendaki panjang tali menjadi 159,5 m, maka modulus Young tali adalah…
Correct Answer
A. 2 x 108 N/m2
Explanation
The correct answer is 2 x 108 N/m2. This can be determined using the formula for Young's modulus, which is stress divided by strain. In this case, the strain is the change in length of the rope (159.5 m - 157 m = 2.5 m) divided by the original length (157 m). The stress can be calculated by dividing the force applied (mass x gravity) by the cross-sectional area of the rope. Plugging in the given values and solving the equation will yield a Young's modulus of 2 x 108 N/m2.
21.
Dua buah logam A dan B memiliki suhu berbeda di tiap ujungnya disambung menjadi satu. Apabila koefisien konduktivitas logam A adalah ½ koefisien konduktivitas logam B dan PQ = 2QR, maka suhu di Q adalah … °C
Correct Answer
C. 54
Explanation
When two metal rods with different temperatures are connected, heat will flow from the hotter end to the colder end until they reach thermal equilibrium. The rate of heat transfer is determined by the thermal conductivity of the metals. Since the coefficient of thermal conductivity of metal A is half of metal B, it means that metal B conducts heat better than metal A. Therefore, the heat will flow faster from metal A to metal B. Given that PQ = 2QR, it indicates that the temperature difference between P and Q is twice the temperature difference between Q and R. Therefore, if the temperature difference between P and Q is x, then the temperature difference between Q and R is x/2. Since the temperature at P is higher than Q, and the temperature at R is lower than Q, the temperature at Q must be the average of the two, which is (P + R)/2. Therefore, if the correct answer is 54, it means that the temperature at Q is 54 degrees Celsius.
22.
Sebuah motor listrik mengangkat balok besi dengan berat 1,5 kg ke atas setinggi 3m (g = 10 ms-2). Bila tegangan arus, dan efisiensi motor berturut-turut adalah 12,5 V, 1,5 A, dan 60%, waktu yang diperlukan motor listrik di atas (dalam detik) adalah…
Correct Answer
B. 4
Explanation
The question asks for the time required for the electric motor to lift a 1.5 kg iron block to a height of 3m. The weight of the block is given as 1.5 kg and the acceleration due to gravity is given as 10 m/s^2. The work done in lifting the block is equal to the weight of the block multiplied by the height, which is 1.5 kg * 10 m/s^2 * 3m = 45 J. The power output of the motor is equal to the voltage multiplied by the current, which is 12.5 V * 1.5 A = 18.75 W. The time required to do the work is equal to the work divided by the power output, which is 45 J / 18.75 W = 2.4 s, rounded to the nearest whole number is 2. Therefore, the correct answer is 4 seconds.
23.
Gaya Coriolis membelokan arus di bagian bumi utara ke kanan dan arus di bagian bumi selatan ke arah kiri.
Sebab
Perputaran bumi pada porosnya menyebabkan gaya Coriolis.
Correct Answer
A. A
Explanation
The Coriolis force is a result of the Earth's rotation on its axis. This force causes moving objects, such as air or ocean currents, to be deflected to the right in the Northern Hemisphere and to the left in the Southern Hemisphere. Therefore, the statement that the Coriolis force bends currents in the northern part of the Earth to the right and currents in the southern part to the left is correct.
24.
Daratan lebih panas pada siang hari dikarenakan kalor jenis daratan lebih besar daripada kalor jenis lautan.
Sebab
Angin laut bertiup dari laut ke darat pada siang hari.
Correct Answer
D. D
Explanation
The correct answer is D. This is because during the day, the land heats up more quickly than the ocean due to the higher specific heat capacity of land compared to water. As a result, the air above the land becomes warmer and rises, creating a low-pressure area. This causes the cooler air from the ocean to flow towards the land, resulting in the sea breeze phenomenon.
25.
Gaya F sebesar 12 N bekerja pada sebuah benda yang massanya m1 menyebabkan percepatan sebesar 8 ms–2. Jika F bekerja pada benda yang bermassa m2, maka percepatan yang ditimbulkannya adalah 2 m s–2. Jika F bekerja pada benda yang bermassa m1 + m2, maka percepatan benda ini adalah ....
Correct Answer
B. 1,6 m/s2
Explanation
The force F is directly proportional to the acceleration produced on an object. In the given scenario, when F is applied to an object with mass m1, it results in an acceleration of 8 m/s^-2. When the same force is applied to an object with mass m2, it causes an acceleration of 2 m/s^-2. Therefore, the ratio of the accelerations is equal to the ratio of the masses (m1/m2). Now, if the force is applied to an object with a combined mass of m1 + m2, the resulting acceleration can be calculated by multiplying the ratio of the masses (m1/m2) with the acceleration produced on the object with mass m2 (2 m/s^-2). Thus, the acceleration of the object with mass m1 + m2 is 1.6 m/s^2.
26.
Untuk menentukan percepatan sebuah kereta, digantungkan sebatang tongkat homogen pada langit-langit gerbong kereta. Ketika kereta bergerak dengan percepatan sebesar a, tongkat pada posisi condong membentuk sudut p terhadap arah vertikal. Hubungan antara a dan p adalah ....
Correct Answer
C. A = g tg p
Explanation
The given answer, "a = g tg p," is the correct equation to determine the relationship between acceleration (a) and the angle (p) formed by the inclined stick. This equation is derived from the trigonometric relationship between the acceleration due to gravity (g), the angle (p), and the tangent function (tg). The tangent function relates the opposite side (a) to the adjacent side (g) of a right triangle, which in this case represents the components of acceleration along the inclined stick and perpendicular to it. Therefore, the correct equation is a = g tg p.
27.
Sebuah benda bermassa 0,25 kg jatuh dengan percepatan 9,2 m/s2. Apabila dianggap gaya gesekan udara konstan, maka besarnya gaya ini adalah ....
Correct Answer
A. 0,2 N
Explanation
The force of friction is given by the equation F = μN, where μ is the coefficient of friction and N is the normal force. In this case, the normal force is equal to the weight of the object, which is given by the equation N = mg, where m is the mass of the object and g is the acceleration due to gravity. Since the object is falling, the normal force is equal to the weight, and the force of friction is μmg. Given that the mass of the object is 0.25 kg and the acceleration due to gravity is 9.8 m/s^2, the force of friction is 0.2 N.
28.
Dua kapasitor masing-masing dengan kapasitas 2 uF dan 3 uF dipasang secara seri. Beda potensial antara ujung-ujung gabungan 10 volt. Besar muatan pada kapasitor 2 uF adalah ...
Correct Answer
B. 12 uC
Explanation
When capacitors are connected in series, the total capacitance is given by the reciprocal of the sum of the reciprocals of individual capacitances. In this case, the total capacitance is 1/Ctotal = 1/C1 + 1/C2 = 1/2uF + 1/3uF = 5/6uF.
The charge on a capacitor is given by Q = CV, where Q is the charge, C is the capacitance, and V is the voltage.
Given that the potential difference across the combination is 10 volts, we can calculate the charge on the 2uF capacitor as Q = (5/6uF)(10V) = 50/6uC = 8.33 uC.
However, since the answer choices are limited to whole numbers, the closest option is 12 uC.
29.
Sebuah atom akan memancarkan sebuah foton apabila salah satu elektronnya mengalami transisi ke tingkat energi yang lebih tinggi
SEBAB
Transisinya terjadi pada perpindahan elektron dari tingkat energi rendah ke tingkat energi yang lebih tinggi
Correct Answer
E. E
Explanation
An atom will emit a photon when one of its electrons undergoes a transition to a higher energy level. This is because the transition occurs when the electron moves from a lower energy level to a higher energy level.
30.
Induktansi selenoida dapat diperbesar dengan cara
1. menambah jumlah lilitan
2. memperbesar diameter
3. memperpendek panjang
4. memperbesar tegangan sumber
Correct Answer
A. A
Explanation
The correct answer is A because increasing the number of turns in a solenoid coil will increase its inductance. This is because each turn of the coil contributes to the overall magnetic field produced by the solenoid, resulting in a larger inductance value.
31.
Gas X sebanyak 0,20 gram menempati volume 440 mL. Jika 0,10 g gas CO2 pada T dan P yang sama menempati volume 320 mL, maka gas X tersebut adalah …. (Ar C = 12, N = 14, O = 16, S = 32 )
I. O2
II. SO2
III. SO3
IV. NO2
V. NO
Correct Answer
B. II
Explanation
Gas X is determined by comparing the volume of the given gas (0.20 g) to the volume of CO2 (0.10 g) at the same temperature and pressure. Since the volume of CO2 is smaller than the volume of Gas X, it suggests that Gas X has a higher molar mass than CO2. Among the given options, only SO2 has a higher molar mass than CO2, so the correct answer is II.
32.
Jika 0,56 g logam M bereaksi denga HCl (aq) dan membentuk 0,005 mol gas H2 dan larutan MCl2
maka massa atom relatif M adalah ....
Correct Answer
E. 112
Explanation
The given question states that 0.56 g of metal M reacts with HCl to form 0.005 mol of H2 gas and MCl2 solution. From the given information, we can calculate the molar mass of M by using the formula:
Molar mass = (mass of M)/(moles of M)
Given that the mass of M is 0.56 g and the moles of M is 0.005 mol, we can calculate the molar mass as:
Molar mass = 0.56 g / 0.005 mol = 112 g/mol
Therefore, the mass of the relative atomic mass of M is 112.
33.
Senyawa yang termasuk alkohol tersier adalah ….
Correct Answer
B. 2-metil-2-propanol
Explanation
2-metil-2-propanol adalah senyawa yang termasuk alkohol tersier karena pada molekulnya terdapat tiga gugus alkil yang terikat pada atom karbon yang terikat pada atom oksigen. Dalam hal ini, terdapat tiga gugus metil (CH3) yang terikat pada atom karbon yang terikat pada atom oksigen, sehingga membuatnya menjadi alkohol tersier.
34.
Di bawah ini yang merupakan molekul dengan ikatan kovalen rangkap tiga adalah…
Correct Answer
E. N2 (Nomor atom N = 7)
Explanation
Molekul dengan ikatan kovalen rangkap tiga terjadi ketika dua atom berbagi tiga pasang elektron. Dalam pilihan yang diberikan, hanya N2 (nitrogen) yang memiliki nomor atom 7. Oleh karena itu, N2 adalah molekul dengan ikatan kovalen rangkap tiga.
35.
Apabila
2 H2(g) + O2(g) 2 H2O(g) = a kJ
2 Ca(s) + O2(g) 2 CaO(s) = b kJ
CaO(s) + H2O(g) Ca(OH)2(s) = c kJ
Besar pembentukan Ca(OH)2(s) adalah…
Correct Answer
E. 1/2 a + 1/2 b + c
Explanation
The given chemical equations represent the formation of water (H2O), calcium oxide (CaO), and calcium hydroxide (Ca(OH)2) from their respective reactants. The enthalpy change (heat released or absorbed) for each reaction is given as a, b, and c kJ, respectively. The question asks for the enthalpy change for the formation of Ca(OH)2. To find this, we add the enthalpy changes of the individual reactions: 1/2 a + 1/2 b + c.
36.
Pada sebuah generator, direaksikan 25,2 gram CaH2 dengan air sebagaimana digambarkan dalam reaksi berikut:
CaH2(s) + 2H2O (l) Ca(OH)2(aq) + 2H2(g)
Gas hidrogen diukur pada P dan T di mana pada keadaan tersebut 16 gram oksigen memiliki volume 10 liter. Bila diketahui Ar H = 1, O = 16, Ca = 40, volume gas hidrogen yang dihasilkan adalah…
Correct Answer
D. 24,0 L
Explanation
The given reaction shows that 1 mole of CaH2 produces 2 moles of H2 gas. From the given information, we know that 16 grams of oxygen gas has a volume of 10 liters. Since the molar mass of oxygen is 16 g/mol, we can calculate the number of moles of oxygen gas using the formula: moles = mass/molar mass. Therefore, the number of moles of oxygen gas is 16/16 = 1 mole. Since 1 mole of oxygen gas is equal to 2 moles of H2 gas, the volume of H2 gas produced would be twice the volume of oxygen gas, which is 2 * 10 = 20 liters. However, the question asks for the volume of H2 gas produced by reacting 25.2 grams of CaH2. To find the volume, we need to calculate the number of moles of CaH2 using the formula: moles = mass/molar mass. The molar mass of CaH2 is 40 + 2 = 42 g/mol. Therefore, the number of moles of CaH2 is 25.2/42 = 0.6 moles. Since 1 mole of CaH2 produces 2 moles of H2 gas, the volume of H2 gas produced by reacting 0.6 moles of CaH2 would be 2 * 0.6 = 1.2 liters. Therefore, the correct answer is 24.0 L, which is the volume of H2 gas produced by reacting 25.2 grams of CaH2.
37.
Diketahui 5B, 9F, 14Si, 16S, 54Xe.
Di bawah ini, pasangan senyawa yang memenuhi aturan oktet adalah…
Correct Answer
A. BF4- dan SiF4
Explanation
The correct answer is BF4- and SiF4 because both compounds have a total of 8 valence electrons around the central atom, satisfying the octet rule. In BF4-, the boron atom forms covalent bonds with four fluorine atoms, each contributing one electron to the bond. This results in a total of 8 valence electrons around the boron atom. Similarly, in SiF4, the silicon atom forms covalent bonds with four fluorine atoms, resulting in a total of 8 valence electrons around the silicon atom.
38.
Di bawah ini yang bukan merupakan sifat dari logam alkali adalah…
Correct Answer
A. Terdapat di alam dalam keadaan bebas
Explanation
Logam alkali umumnya tidak ditemukan dalam keadaan bebas di alam karena mereka sangat reaktif dan mudah bereaksi dengan oksigen atau air. Mereka biasanya ditemukan dalam bentuk senyawa seperti garam. Oleh karena itu, pernyataan "Terdapat di alam dalam keadaan bebas" bukan merupakan sifat dari logam alkali.
39.
Titik didih CH3 – O – CH3 lebih tinggi dibanding C2H5OH.
Sebab
CH3 – O – CH3 lebih polar bila dibandingkan dengan C2H5OH.
Correct Answer
E. E
Explanation
The boiling point of CH3-O-CH3 is higher than that of C2H5OH because CH3-O-CH3 is more polar compared to C2H5OH.
40.
Dalam 15,9 gram tembaga (I) sulfida (Ar Cu = 63,5 dan S = 32) terdapat Cu sebanyak...
Correct Answer
B. 12,70 gram
Explanation
In 15.9 grams of copper sulfide (CuS), the atomic mass of copper (Cu) is 63.5 and the atomic mass of sulfur (S) is 32. To find the amount of copper (Cu) in 15.9 grams of copper sulfide, we need to calculate the percentage of copper in the compound. The molar mass of copper sulfide is 63.5 + 32 = 95.5 g/mol. The molar mass of copper is 63.5 g/mol. Therefore, the percentage of copper in copper sulfide is (63.5/95.5) * 100 = 66.5%. To find the amount of copper in 15.9 grams of copper sulfide, we multiply the percentage of copper by the total mass of copper sulfide: (66.5/100) * 15.9 = 10.58 grams. Therefore, the answer is 12.70 grams, which is the closest option.
41.
Manakah
reaksi kesetimbangan di bawah ini yang menghasilkan lebih banyak produk jika
tekanan diperbesar ?
Correct Answer
E. 2NO(g) +O2(g) ⇌ 2NO2(g)
Explanation
The reaction 2NO(g) + O2(g) ⇌ 2NO2(g) will produce more products when the pressure is increased. This is because increasing the pressure will shift the equilibrium towards the side with fewer moles of gas. In this reaction, there are 3 moles of gas on the left side and 2 moles of gas on the right side. By increasing the pressure, the equilibrium will shift to the right side to reduce the pressure, resulting in the production of more NO2.
42.
Perhatikan percobaan berikut ini!
Sebanyak 5 gram logam magnesium masing masing dilarutkan dalam 5 wadah yang berbeda.
Laju reaksi yang hanya dipengaruhi oleh konsentrasi terdapat pada tabung nomor….
Correct Answer
E. 4 terhadap 5
Explanation
The correct answer is 4 terhadap 5. This means that the reaction rate is only affected by the concentration of the fourth container compared to the fifth container. This implies that the reaction rate is not influenced by the concentrations of the other containers.
43.
Lemak merupakan molekul yang bersifat polar
SEBAB
Lemak merupakan ester gliserol dari asam karboksilat berantai panjang
Correct Answer
D. D
Explanation
The correct answer is D. Lemak merupakan ester gliserol dari asam karboksilat berantai panjang. This statement explains that fats are glycerol esters of long-chain carboxylic acids. This supports the previous statement that fats are polar molecules.
44.
Diketahui
Pada keadaan standar, pernyataan yang benar untuk reaksi
adalah
1. Reaksi berlangsung spontan
2. Potensial reaksi adalah +1,217 V
3. Reaksi melibatkan 2 elektron
4. Pb merupakan reduktor
Correct Answer
E. E
Explanation
The correct answer is E.
The given information states that "Pb merupakan reduktor" which translates to "Pb is a reducing agent." This means that Pb is capable of donating electrons to another species and getting oxidized in the process. Therefore, option E is the correct answer as it states that Pb is a reducing agent.
45.
Konfigurasi ion besi (III), 26Fe3+, mempunyai elektron tidak berpasangan sebanyak…
Correct Answer
D. Lima
Explanation
The configuration of iron (III) ion, 26Fe3+, indicates that there are five unpaired electrons.
46.
Kemungkinan untuk memperoleh keturunan dengan genotip aabbcc dari perkawinan AaBbCc >< AaBbCc adalah...
Correct Answer
E. 1/64
Explanation
Jumlah gamet dari AaBbCc adalah masing-masing 8. DIsilangkan sesamanya menghasilkan 64 keturunan. Yang homozigot resesif hanya 1. Jadi jawaban E.
47.
Sel saraf yang berfungsi mengirimkan impuls dari sistem saraf pusat ke otot dan kelenjar, adalah...
Correct Answer
C. Neuron eferen
Explanation
Berdasarkan fungsinya, sel saraf (neuron) dibedakan menjadi 3, yaitu:
1. Sel saraf sensori (neuron aferen), berfungsi untuk menghantarkan impuls dari reseptor (indra) ke saraf pusat (otak dan sumsum tulang belakang)
2. Sel saraf motoris (neuron eferen), berfungsi untuk menghantarkan impuls dari saraf pusat ke efektor (otot dan kelenjar).
3. sel saraf penghubung (neuron intermedier), berfungsi untuk menghubungkan neuron yang satu ke neuron yang lainnya.
Neuroglia merupakan kelompok sel yang berfungsi untuk memberikan nutrisi dan bahan untuk hidupnya neuron sehingga neuron tersebut dapat melakukan aktivitasnya. Jawab C.
48.
Aliran darah yang bergerak paling lambat terjadi pada...
Correct Answer
B. Aorta
Explanation
Aliran darah berbanding terbalik dengan ukuran pembuluh darah sehingga aliran darah yang bergerak paling lambat terjadi pada pembuluh darah yang mempunyai ukuran paling besar. Dari kelima macam pembuluh darah tersebut, pembuluh darah yang berukuran paling besar adalah aorta. Jawab B.
49.
Instabilitas yang menanggapi rangsangan sentuhan disebut...
Correct Answer
B. Tigmotropisme
Explanation
fototropisme, instabilitas yang menanggapi rangsang cahaya
hidrotropisme, gerak bagian tumbuhan yang arahnya ditentukan oleh air atau faktor kelembaban
kemotropisme, gerak bagian tumbuhan yang disebabkan atas rangsang kimia
geotropisme, gerak pada tumbuhan yang disebabkan oleh gaya tarik bumi
50.
Pada tahapan tertentu dari siklus hidup Fasciola hepatica memerlukan keong air tawar Lymnaea sebagai hospes perantara. Nama tahapan tersebut adalah...
Correct Answer
C. Mirasidium
Explanation
Siklus hidup cacing hati:
Telur --> mirasidium (masuk ke dalam siput air) --> redia --> serkaria --> metaserkaria--> kista -->hewan dewasa (termakan oleh hewan/manusia) -->telur