Quiz on Acids and Bases

What do red blood cells deliver to the tissues?

• Nutrients

• Oxygen

• Carbon dioxide

• Hormones

Which of the following is a strong acid mentioned in the list?

• 5% Vinegar

• 5% Sulfuric acid

• 5% Lye

• Phenolphthalein solution

What is the concentration of lye (sodium hydroxide) in the water solution?

• 2%

• 5%

• 10%

• 20%

What should be placed in front of each beaker?

• Cotton ball

• Gauze pad

• Paper towel

• Sponge

What is the final step in the Phenolphthalein test?

• Add 1-2 drops of 95% ethanol

• Add 1-2 drops of Phenolphthalein reagent

• Add 1-2 drops of 3% H2O2

• Observe color change

What does a bright pink color indicate in the Phenolphthalein test?

• Negative result for blood

• Positive result for blood

• Contaminated sample

• Inconclusive result

Which chemical is used to initiate the color change in the Phenolphthalein test?

• 95% ethanol

• Phenolphthalein reagent

• 3% H2O2

• Water

What is the second step in the Phenolphthalein test?

• Add 1-2 drops of 3% H2O2

• Add 1-2 drops of Phenolphthalein reagent

• Add 1-2 drops of 95% ethanol

• Observe color change

What is the purpose of the cotton swabs in the image?

• Cleaning

• Stirring

• Testing

• Measuring

How long was the lye solution observed?

• 2 minutes

• 5 minutes

• 10 minutes

• 15 minutes