Acids, Bases, and salts

What happens when acid reacts with metal?

• Salt + Oxygen gas are formed.

• Salt + Hydrogen gas are formed.

• Salt + Carbon dioxide are formed.

• Salt + Water are formed.

Use of baking soda?

• Baking

• Fire extinguishers

• Antacids

• Cleaning windows

Why do acids conduct electricity?

• Due to presence of free H⁺ ions in solution.

• Because they contain metal ions.

• Because they are always in liquid form.

• Due to the presence of free electrons.

What is the use of bleaching powder?

• Disinfection and bleaching agent.

• Fertilizer for plants.

• Food preservative.

• Water softener.

Test for ammonia gas?

• Pungent smell, turns moist red litmus blue.

• Sweet smell, turns moist blue litmus red.

• No smell, remains unchanged on litmus paper.

• Foul smell, turns moist blue litmus green.

Effect of acid on blue litmus?

• Turns red

• Turns blue

• Remains unchanged

• Turns green

Why does soap feel slippery?

• Due to basic nature (presence of alkali)

• Due to high acidity

• Due to the presence of oils

• Due to low temperature

How is indigestion treated?

• With antacids (mild bases)

• By drinking hot water

• With antibiotics

• By fasting for 24 hours

Why does dry HCl not show acidic property?

• HCl is a gas at room temperature.

• HCl needs water to release H⁺ ions.

• HCl is a weak acid.

• HCl does not dissociate in dry conditions.

Base + Acid → ?

• Salt + Water (Neutralization)

• Gas + Heat

• Base + Base

• Acid + Acid