2.1 2.2 Chemistry CP review

Match the subatomic particles with their charges and locations.

• center of the atom

• positive

• neutral charge

• neutron

• positive charge

• nucleus

• negative charge

• proton

• charge of a proton

• electron

Using the image above (from the periodic table), answer the following: What is the atomic number of Carbon?

• 6

• 8

• 10

• 12

Answer explanation

The atomic number of an element is the number of protons in its nucleus. For Carbon, this number is 6, which is why the correct answer is 6.

Tags

NGSS.MS-PS1-1

Using the image above (from the periodic table), answer the following: What is the atomic mass of Oxygen?

• 15.999

• 12.011

• 1.008

• 14.007

Answer explanation

The atomic mass of Oxygen is approximately 15.999, which is the most accurate value found on the periodic table. The other options represent the atomic masses of different elements.

Using the image above (from the periodic table), answer the following: What is the symbol for Oxygen?

• O

• C

• N

• H

Answer explanation

The symbol for Oxygen is 'O', which is found in the periodic table. The other options represent different elements: 'C' for Carbon, 'N' for Nitrogen, and 'H' for Hydrogen.

Electrons are in constant motion around the nucleus.

• True

• False

Answer explanation

Electrons are indeed in constant motion around the nucleus, forming electron clouds or orbitals. This motion is a fundamental aspect of atomic structure, confirming that the statement is true.

The atomic symbol for Chlorine is C.

• True

• False

Answer explanation

The atomic symbol for Chlorine is Cl, not C. Therefore, the statement is false.

Tags

NGSS.MS-PS1-1

2 Hydrogen atoms and one Oxygen are bonded together to make a water molecule (H₂O).

• True

• False

Answer explanation

The statement is true because a water molecule (H₂O) consists of two hydrogen atoms bonded to one oxygen atom, which is the correct chemical composition of water.

Tags

NGSS.MS-PS1-1

In an ionic bond, electrons are transferred from one atom to another (meaning electrons are taken or received between atoms).

• True

• False

Answer explanation

True. In an ionic bond, one atom donates electrons to another, resulting in the formation of charged ions. This transfer of electrons is a key characteristic of ionic bonding.

Tags

NGSS.MS-PS1-2

Which type of bond is indicated by the image?

• Ionic

• Covalent

• Hydrogen

Answer explanation

The image likely depicts a covalent bond, where atoms share electrons. This is distinct from ionic bonds, which involve electron transfer, and hydrogen bonds, which are weaker interactions. Thus, the correct answer is covalent.

Match the following descriptions with the correct pH scale regions.

• pH scale where is pH neutral

• 7.0

• basic pH range

• 0-6.9

• acidic pH range

• 7.1-14

Answer explanation

The pH scale ranges from 0 to 14. Acids are from 0 to 6.9, neutral is at 7.0, and bases range from 7.1 to 14. Thus, the correct choice is Acid: 0-6.9, Neutral: 7.0, Base: 7.1-14.