Chemistry Assessment

How many protons are found in the nucleus of sodium?

• twelve

• eleven

• thirteen

• fifteen

Group 0 elements are unreactive because

• they do not have electrons

• they have many protons

• their shells are fully filled

• their shells are partially filled

What is the relative formula mass of Na₂CO₃?

[Na = 23 C = 12 O = 16]

• 106g/mol

• 216 g/mol

• 102 g/mol

• 200 g/mol

Which of the following elements is a noble gas?

• Oxygen

• Neon

• Hydrogen

• Carbon

What is the chemical formula for calcium carbonate?

• CaCO₃

• Ca₂CO₃

• CaO

• Ca₃CO₂

How many electrons are in a neutral atom of chlorine?

• 17

• 18

• 16

• 15

The release of a pop sound confirms which of the following gases?

• Oxygen

• Chlorine

• Carbon dioxide

• hydrogen

Calcium hydroxide becomes milky when ---------- is passed through it.

• hydrogen

• oxygen

• carbon dioxide

• ammonia

What is the atomic number of potassium?

• 19

• 21

• 18

• 20

Which of the following compounds is an acid?

• NaCl

• CaCO₃

• HCl

• NaOH