In a laboratory experiment, John uses a mesh to separate soil particles from water. Which technique of separation is he using?

Water levels tend to drop in dry weather because of evaporation. The hot temperatures will cause the water to achieve its gaseous state and go up into the atmosphere.

6 0

3 years ago

Which type of allergy test, also called a subcutaneous test, introduces dilute solutions of allergens into the skin of the inner

alexgriva [62]

Answer:

The type of allergy test is scratch test.

Explanation:

In a scratch test also called a skin pri c k test or puncture test, an allergy provoking substance placed on the skin is gradually scratched into the skin surface with the aid of a needle or lancet so as to detect bodily reactions to allergens. Some of the types allergens whose reactions are generally tested for include pollen, dust mites, molds and foods.

The scratch test takes about 5 to 10 minutes and it could cause slight pain and the may result in itching feeling at the location where the allergen was introduced.

6 0

3 years ago

PLEASE HELP WILL GIVE BRAINLYIST TO FIRST PERSON

kolezko [41]

Answer:

1) Weak base.

2) Weak acid.

Explanation:

1) Which would have a lower pH, a 0.1 M solution of a strong base or a weak base? Why?

For bases:

Solution with lower pH means that the solution has a lower basic character.

While solution with higher pH means that the solution has a higher basic character.

When we have a 0.1 M solution of a strong base or a weak base, the weak base will have a lower pH because it is not completely dissociated to produce OH⁻ ions.

While, strong base dissociates completely to produce OH⁻ ions, so it will has higher basic character and thus has a higher pH value.

So, weak base will have the lower pH value.

2) Which would have a higher pH, a 0.1 M solution of a strong acid, or a weak acid? Why?

For Acids:

Solution with lower pH means that the solution has a higher acidic character.

While solution with higher pH means that the solution has a lower acidic character.

When we have a 0.1 M solution of a strong acid or a weak acid, the weak acid will have a higher pH because it is not completely dissociated to produce H⁺ ions, so it has a lower acidic character.

While, strong acid dissociates completely to produce H⁺ ions, so it will has higher acidic character and thus has a lower pH value.

So, weak acid will have the higher pH value.

5 0

2 years ago