1.
Carbon tetrachloride
Correct Answer
B. CCl4
Explanation
Carbon tetrachloride is represented by the chemical formula CCl4. The prefix "tetra" indicates that there are four chlorine atoms bonded to a central carbon atom. Therefore, option CCl4 is the correct representation of carbon tetrachloride. The other options, CaCl4, Ca4Cl, and C4Cl, do not accurately represent the composition or structure of carbon tetrachloride.
2.
Copper (II) oxide
Correct Answer
A. CuO
Explanation
Copper (II) oxide is represented by the chemical formula CuO. The Roman numeral II in the name indicates that copper has a +2 oxidation state in this compound. The formula Cu2O represents copper (I) oxide, where copper has a +1 oxidation state. CuO2 and Cu2O2 are incorrect formulas and do not represent any known compounds. Therefore, the correct answer is CuO.
3.
Sodium hypochlorite
Correct Answer
D. NaClO
Explanation
Sodium hypochlorite is represented by the formula NaClO. The formula indicates that it is composed of one sodium atom (Na), one chlorine atom (Cl), and one oxygen atom (O). The subscript of 1 for each element indicates that there is only one atom of each element in the compound. Therefore, the correct answer is NaClO.
4.
Aluminum hydroxide
Correct Answer
A. Al(OH)3
Explanation
The correct answer is Al(OH)3 because aluminum hydroxide is a compound that consists of one aluminum atom bonded with three hydroxide ions. The chemical formula Al(OH)3 accurately represents this composition, while the other options do not. Al(OH)2 represents a compound with only two hydroxide ions, AlOH represents a compound with only one hydroxide ion, and AlO represents a compound without any hydroxide ions. Therefore, Al(OH)3 is the correct formula for aluminum hydroxide.
5.
Copper (II) sulfate pentahydrate
Correct Answer
C. CuSO4 . 5H2O
Explanation
The correct answer is CuSO4 . 5H2O. This is because the compound is copper (II) sulfate pentahydrate, which is represented by the chemical formula CuSO4 . 5H2O. The formula Cu2(SO4)2 .5H2O is incorrect because it suggests that there are two copper atoms and two sulfate ions, which is not the case.
6.
Potassium permanganate
Correct Answer
B. KMnO4
Explanation
Potassium permanganate is represented by the chemical formula KMnO4. The correct answer, KMnO4, matches the given chemical formula. The other options, KMnO5, KMnO3, and KMnO2, do not match the correct chemical formula for potassium permanganate.
7.
Carbon dioxide
Correct Answer
C. CO2
Explanation
The correct answer is CO2. Carbon dioxide is a chemical compound composed of one carbon atom bonded to two oxygen atoms. The formula CO2 represents this composition accurately. The other options provided in the question, C2O, CO3, and CO, do not correctly represent the composition of carbon dioxide.
8.
Hydrochloric acid
Correct Answer
D. HCl
Explanation
Hydrochloric acid is represented by the chemical formula HCl, which matches the given answer. HClO4, HClO, and HClO3 are not hydrochloric acid, but rather perchloric acid, hypochlorous acid, and chloric acid respectively. Therefore, the correct answer is HCl.
9.
Hyposulfurous acid
Correct Answer
D. H2SO2
Explanation
H2SO2 is the correct answer because it corresponds to the compound hyposulfurous acid. The formula H2SO2 indicates that the acid contains two hydrogen atoms and one sulfur atom. The prefix "hypo-" suggests that the acid has one less oxygen atom than the related sulfuric acid (H2SO4). Therefore, H2SO2 is the appropriate formula for hyposulfurous acid.
10.
Ammonium acetate
Correct Answer
A. NH4C2H3O2
Explanation
Ammonium acetate is a compound that consists of the ammonium ion (NH4+) and the acetate ion (C2H3O2-). The formula NH4C2H3O2 represents one ammonium ion and one acetate ion, which is the correct formula for ammonium acetate. The other options either have incorrect subscripts or include multiple ammonium or acetate ions, which would result in a different compound.