Latihan Soal Bab Hakikat Ilmu Kimia

The correct answer is C. Tangan dialiri air terus-menerus. When the hand is exposed to hazardous chemicals, the first aid that should be given is to continuously flush the hand with water. This helps to remove the chemical from the skin and dilute it, reducing the risk of further damage or absorption into the body. Applying toothpaste, blowing until dry, using high-concentration alcohol, or wiping with tissue are not appropriate first aid measures for chemical exposure.

The symbol in the picture indicates that the substance is corrosive. Corrosive substances have the ability to destroy or damage other materials or living tissues through chemical reactions. Therefore, option D is the correct answer.

The question asks for something that does not belong in the systematic writing of a scientific report. The options A, B, C, and D are all components that are typically included in the systematic structure of a scientific report. However, option E, "wawancara" (interview), is not a part of the systematic structure of a scientific report. Therefore, option E is the correct answer.

The correct answer is C. Merumuskan masalah. In conducting research, the first step is to formulate a clear and specific research problem. This involves identifying the scope and nature of the problem, as well as determining the objectives and goals of the research. By formulating a research problem, researchers can define the focus of their study and develop appropriate research questions and hypotheses. This step is crucial as it sets the foundation for the entire research process and helps guide the collection and analysis of data.

The correct answer is E because it is the safest method of heating a substance using a test tube and clamp. By holding the clamp, the person can control the movement and positioning of the test tube while heating it. The test tube is heated while being gently shaken or tapped to ensure even distribution of heat and prevent the substance from boiling over or splattering. Additionally, the person ensures that the mouth of the test tube is directed away from themselves and others to prevent any potential accidents or injuries.

The isotope 55Mn25 has 25 electrons because the atomic number of manganese (Mn) is 25, which represents the number of electrons in a neutral atom. It has 25 protons because the atomic number also represents the number of protons. The atomic mass of 55Mn is 55, so it has 30 neutrons (55 - 25 = 30). Therefore, the correct answer is A. 25, 25, 30.

The atomic number of an element represents the number of protons in its nucleus. Since the atomic number of Ni is 28, the ion Ni2+ would have 28 protons. The number of electrons in an ion is determined by the charge of the ion, which in this case is 2+. Therefore, there would be 2 fewer electrons than protons, resulting in 26 electrons. The mass number of an element represents the total number of protons and neutrons in its nucleus. Since the mass number of Ni is 59, and we already know that there are 28 protons, the number of neutrons can be calculated by subtracting the number of protons from the mass number: 59 - 28 = 31 neutrons. Therefore, the correct answer is C. 28, 26, 31.

The elements 146C and 147N are considered isobars because they have the same mass number but different atomic numbers. Isobars are atoms of different elements that have the same mass number but different atomic numbers, meaning they have different numbers of protons. In this case, carbon-146 (146C) has 6 protons and nitrogen-147 (147N) has 7 protons, but they both have a mass number of 146, which is the sum of protons and neutrons.

The correct answer is A. 18O dan 19F mempunyai jumlah neutron yang sama. This statement is correct because both oxygen-18 (18O) and fluorine-19 (19F) have the same number of neutrons, which is 10. The number of neutrons in an atom is determined by subtracting the atomic number (which represents the number of protons) from the atomic mass (which represents the total number of protons and neutrons). In this case, both 18O and 19F have an atomic mass of 18 and 19 respectively, and since their atomic numbers are 8 and 9, it means they both have 10 neutrons.