Question

Isotopes/Molecules/Compounds, Select true or false for the
following questions:
Isotopes are atoms of the same element, with a different number of protons. ___
Unstable isotopes emit energy called radiation.
___
Radiation is good for cells, preventing cancer.
___
A molecule is simply atoms bonded together. ___
A compound is when two or more atoms of different elements chemically combine.
___
Atom Bonding, Fill in the blank for the following questions:
Electrons orbit around the nucleus in __________.
Atoms are most stable when their outer electron shell, the
__________
shell is full.
For atoms with atomic numbers of 18 elements or less, the first shell can only hold up to
__________
electrons. Then the second and third shell can hold up to
__________
electrons.
Ions are
__________ charged atoms because it has gained or lost one or more electrons.
Cations are
__________ charged because they have
__________
electrons.
Anions are
__________ charged because they have
__________
electrons.
Therefore, an ionic bond is the attraction between a/an
__________
and a/an__________. In
which electrons are transferred.
A covalent bond on the other hand, are atoms that
__________
electrons to fill their valance
shells.
Polar molecules are a result of
__________
bonds. Where electrons are not shared equally.
Hydrogen bonds are weak attractions between the
__________
end of one polar molecule and
the
__________
end another polar molecule.
Electrolytes, Fill in the blank for the following questions:
Electrolytes are substances that release ions in __________.
Acids are substances that dissociate in water, releasing __________
ions (H+).
Bases are substances that release hydroxide ions (OH-), that can combine with
__________

Answer 1

Sure, here are the answers based on your questions:

**Isotopes/Molecules/Compounds: True or False**

1. Isotopes are atoms of the same element, with a different number of protons. **False** (Isotopes have the same number of protons but a different number of neutrons).
2. Unstable isotopes emit energy called radiation. **True**
3. Radiation is good for cells, preventing cancer. **False** (Radiation can be harmful to cells and is a known risk factor for cancer).
4. A molecule is simply atoms bonded together. **True**
5. A compound is when two or more atoms of different elements chemically combine. **True**

**Atom Bonding: Fill in the blank**

1. Electrons orbit around the nucleus in **energy levels (or shells)**.
2. Atoms are most stable when their outer electron shell, the **valence** shell is full.
3. For atoms with atomic numbers of 18 elements or less, the first shell can only hold up to **2** electrons. Then the second and third shells can hold up to **8** electrons.
4. Ions are **charged** atoms because it has gained or lost one or more electrons.
5. Cations are **positively** charged because they have **lost** electrons.
6. Anions are **negatively** charged because they have **gained** electrons.
7. Therefore, an ionic bond is the attraction between a/an **cation** and a/an **anion** in which electrons are transferred.
8. A covalent bond on the other hand, are atoms that **share** electrons to fill their valence shells.
9. Polar molecules are a result of **covalent** bonds, where electrons are not shared equally.
10. Hydrogen bonds are weak attractions between the **partial positive** end of one polar molecule and the **partial negative** end of another polar molecule.

**Electrolytes: Fill in the blank**

1. Electrolytes are substances that release ions in **solution (or water)**.
2. Acids are substances that dissociate in water, releasing **hydrogen** ions (H+).
3. Bases are substances that release hydroxide ions (OH-), that can combine with **hydrogen ions (H+)**.