Y7 C2 L3 Compounds

Is Mg an element or a compound?

• Element

• Compound

Answer explanation

Mg is the symbol for magnesium. You can tell it's an element because there is only one capital letter (each element only has one capital letter in its symbol)

Is Na an element or a compound?

• Element

• Compound

Is H₂O an element or a compound?

• Element

• Compound

Answer explanation

This is water - a compound of hydrogen and oxygen - you can tell because there are two capital letters in the formula; each one comes from a different element symbol.

Is NaCl an element or a compound?

• Element

• Compound

Which of the following are elements?

• Ca

• CO₂

• O₂

• H₂O

Which of the following are compounds?

• NaCl

• Cu

• C₆H₁₂O₆

• Fe

What's the difference between a mixture of sodium and chlorine and the compound sodium chloride?

• In the mixture, the atoms are not joined together, whereas in the compound they are joined together

• In the mixture, the atoms are joined together, whereas in the compound they are not joined together

Water is a compound. Which statement best describes water?

• Water contains more than one different atom chemically joined together

• Water contains more than one different atom but not joined together

• Water contains only one type of atom

• Water contains more than one atom of the same type, joined together

Gold is an element. Which statement best describes gold?

• Gold contains only one type of atom

• Gold contains more than one type of atom, but not joined together

• Gold contains more than one type of atom joined together

• Gold is not a compound

Carbon dioxide contains an atom of carbon joined to two atoms of oxygen. Which statement best describes carbon dioxide?

• Carbon dioxide is a compound

• Carbon dioxide is an element

• Carbon dioxide is an atom

• Carbon dioxide is a mixture