Question

1. discuss the three main subatomic particles. where are they located within the atom? what are their relative masses? describe the electrical charge of each.
2. compare neutral atoms and atomic ions.
3. what is a chemical compound?
4. using the periodic table of the elements in appendix c, indicate which element has seven protons.
5. in what three ways can particles in matter be arranged? what kind of particles make up most of the earth’s atmosphere?
6. the compound nh₃ is made up of which elements and how many atoms of each element?
7. describe three ways that matter can change.
8. state the kind of change in matter in each example below:

a. ocean waves and sand erode a sea cave in a solid rock cliff.
b. fallen snow compacts into glacier ice.
c. a solid rock decomposes into a different substance (called clay) from exposure to sun and rain.
d. a sample of radioactive uranium slowly turns into the element lead over a long period of time.
e. a pond dries up.
f. acid rain gradually eats away the features of a limestone statue in new york city.

1. how is the use of nuclear reactions for power generation an example of good and wise dominion science?
2. (true or false) when a log burns, its matter disappears.

Explanation:

1. Sub - atomic particles: Protons (in nucleus, mass ~ 1 amu, +1 charge), neutrons (in nucleus, mass ~ 1 amu, 0 charge), electrons (outside nucleus, mass ~ 1/1836 amu, - 1 charge).
2. Neutral atoms vs ions: Neutral atoms have equal number of protons and electrons. Ions have a charge due to gain or loss of electrons.
3. Chemical compound: A substance formed from two or more different elements chemically bonded in a fixed ratio.
4. Element with seven protons: Nitrogen, as the atomic number (number of protons) is 7.
5. Particle arrangements in matter: Solid (ordered), liquid (less ordered), gas (random). Earth's atmosphere is mainly made of nitrogen and oxygen molecules.
6. NH₃ composition: Nitrogen (1 atom) and hydrogen (3 atoms).
7. Matter changes: Physical change (e.g., change of state), chemical change (formation of new substances), nuclear change (changes in nucleus).
8. Types of change:

• a. Physical change (erosion is a physical process).
• b. Physical change (compaction is a physical process).
• c. Chemical change (decomposition into a different substance).
• d. Nuclear change (radioactive decay).
• e. Physical change (evaporation).
• f. Chemical change (acid - base reaction).

1. Nuclear power and dominion science: Nuclear reactions for power can be seen as a responsible use of natural resources if managed properly, providing clean energy compared to fossil fuels.
2. Burning log: False. Matter is conserved in a chemical reaction like burning, it just changes form.

Answer:

1. Protons are in the nucleus, have a relative mass of about 1 amu and a +1 charge. Neutrons are in the nucleus, have a relative mass of about 1 amu and a 0 charge. Electrons are outside the nucleus, have a relative mass of about 1/1836 amu and a - 1 charge.
2. Neutral atoms have an equal number of protons and electrons. Atomic ions have a net charge due to the gain or loss of electrons.
3. A chemical compound is a substance composed of two or more different elements chemically combined in a fixed ratio.
4. Nitrogen.
5. Particles in matter can be arranged in an ordered (solid), less - ordered (liquid), or random (gas) way. The earth's atmosphere is mainly made up of nitrogen and oxygen molecules.
6. NH₃ is made up of 1 nitrogen atom and 3 hydrogen atoms.
7. Physical change, chemical change, nuclear change.

8.

• a. Physical change
• b. Physical change
• c. Chemical change
• d. Nuclear change
• e. Physical change
• f. Chemical change

1. It can be seen as a responsible use of natural resources for clean energy if managed well.
2. False