chemical substances

The last energy level of metal atoms contains.........

• 1 : 3 electrons

• 3 : 5 electrons

• 5 : 7 electrons

• 8 electrons

The strength of the metallic bond increases with the increasing the number of the.......

• Proton in the nucleus

• Valence electrons

• Energy levels

• Neutrons in the nucleus

The hardest element of the following is...........

• ₁₃ Al

• ₁₇ Cl

• ₁₂ Mg

• ₁₁ Na

The molecular formula of hydrochloric acid is.......

• Hcl

• HClo

• Hclo₂

• Hclo₃

Acids can contain the following atomic groups except.........

• Carbonate group

• Sulphate grougroup

• Nitrate group

• Hydroxide group

Which of the following substances are acids?

• Lemon 🍋 and baking soda

• Ketchup and grapes 🍇

• Soap 🧼 and toothpaste

• Detergents 🧴and ketchup

The compound which is used in antacids is......

• MgCl₂

• Mg(oH)₂

• H₂Co₃

• NaCl