Sources of Food - Acids and alkalines

The following conditions are required for plants to grow and produce food.

1. (a)   ,

2. air,

3. water,

4. soil.

Answer explanation

sunlight is essential for photosynthesis to occur.

Acids turn blue litmus paper red.

• True

• False

Alkaline turn red litmus paper blue.

• True

• False

A neutral solution will turn red litmus paper blue and blue litmus paper red.

• True

• False

Answer explanation

Both blue and red litmus paper will remain unchanged in a neutral solution.

The universal indicator solution will turn __________ in an acidic solution.

• red

• green

• blue

Answer explanation

Just connect red to acids, blue to alkaline and green to neutral.

The universal indicator solution will turn __________ in an alkaline solution.

• red

• green

• blue

Answer explanation

Just connect red to acids, blue to alkaline and green to neutral.

The universal indicator solution will turn __________ in a neutral solution.

• red

• green

• blue

Answer explanation

Just connect red to acids, blue to alkaline and green to neutral.

A pH meter will give a reading of ____ when placed in an acidic solution.

• <7

• 7

• >7

Answer explanation

Less than 7 --> acidic

Neutral --> green

More than 7 --> alkaline

A pH meter will give a reading of ____ when placed in an alkaline solution.

• <7

• 7

• >7

Answer explanation

Less than 7 --> acidic

Neutral --> green

More than 7 --> alkaline

A pH meter will give a reading of ____ when placed in a neutral solution.

• <7

• 7

• >7

Answer explanation

Less than 7 --> acidic

Neutral --> green

More than 7 --> alkaline