Matter Interactions Unit Test Answers

1. The electron has a negative charge and is found outside of the nucleus.
2. The model should show 27 protons and 32 neutrons.
3. The atoms in lithium sulfide are held together by bonds.
4. chlorine (Cl)
5. They have similar reactivity.
6. It is a physical change because there is no reaction.
7. They form new substances.
8. it shows that no atoms have been gained or lost during the reaction
9. 58.44 amu
10. Find the mass of a piece of ice. Let the ice melt. Find the mass of the liquid water.
11. six
12. H2O
13. Do it yourself
14. Do it yourself

These answers are correct for Sep 2024.

1 answer

It seems like you have provided a list of answers for a unit test related to matter interactions. If you're looking for a review, clarification on these concepts, or any further explanations, feel free to ask! Here's a brief overview based on the answers you've provided:

  1. Electrons are negatively charged subatomic particles located outside the nucleus of an atom.
  2. Atomic Models typically show the number of protons and neutrons, which can help determine the mass number of an atom.
  3. Atoms in lithium sulfide are connected by ionic bonds, which are formed between metals and nonmetals.
  4. Chlorine (Cl) is a nonmetal found in Group 17 of the periodic table.
  5. Elements in the same group of the periodic table often have similar reactivity due to their similar electron configurations.
  6. The melting of ice is a physical change because it involves a change of state without altering the substance's chemical identity.
  7. Chemical reactions often result in the formation of new substances as bonds are broken and formed.
  8. The law of conservation of mass states that mass is neither created nor destroyed in a chemical reaction, indicating no atoms are gained or lost.
  9. The atomic mass of an element like Copper (Cu), which is approximately 58.44 amu.
  10. Mass conservation can be illustrated by measuring the mass of ice before and after melting, showing that mass is conserved in physical changes.
  11. The atomic number of carbon is six as it has six protons.
  12. The chemical formula for water is H2O, indicating it consists of two hydrogen atoms bonded to one oxygen atom.
  13. & 14. "Do it yourself" suggests a need for personal engagement in experiments or conclusions.

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