Answer:
Explanation:
The formula for the change in freezing point ΔT_f caused by an electrolyte is
1. Calculate i
Na₂SO₄(aq) ⟶ 2Na⁺(aq) + SO₄²⁻(aq)
1 mol Na₂SO₄ gives 3 mol ions.
i = 3
2. Calculate the freezing point
(a) Change in freezing point
(b) Freezing point
Answer:
A potentiometric pH meter is used to measure the pH of a solution.
Explanation:
A pH meter is an common instrument that is used to measure the hydrogen-ion concentration in aqueous solutions , the meter indicates its acidity or alkalinity and is expressed as pH.
The pH meter measures the difference in electrical potential between a pH electrode and a reference electrode, hence the pH meter is often called a potentiometric pH meter. The difference in electrical potential is related to the pH of the solution.
Potentiometric pH meters consists of a simple electronic amplifier and a pair of electrodes, alternatively it may consist of a combination electrode, and some form of display calibrated in pH units. It usually has a glass electrode and a reference electrode, or a combination electrode. The electrodes, or probes, are inserted into the solution to be tested and pH values are read off.
Answer: highest activity of salivary amylase is at pH 6.8.
Explanation:Amylase enzyme catalyses the hydrolysis of starch into sugars. Amylase is present in the saliva of humans and some other mammals. The enzymatic activity of salivary amylase ranges from 6 to 7. Above and below this range, the reaction rate reduces as enzymes get denaturated. But the optimum enzymatic activity is at pH 6.8.
From high temperature to low temperature.