Answer:An endothermic reaction
Explanation: In an endothermic reaction, it takes more energy to break the bonds of the reactants than is released when the bonds in the products are formed. In an endothermic reaction, the temperature goes down.
Answer: 0.172 M
Explanation:
a) To calculate theconcentration of base, we use the equation given by neutralization reaction:

where,
are the n-factor, molarity and volume of acid which is 
are the n-factor, molarity and volume of base which is NaOH.
We are given:

Putting values in above equation, we get:

b) To calculate the concentration of acid, we use the equation given by neutralization reaction:

where,
are the n-factor, molarity and volume of acid which is 
are the n-factor, molarity and volume of base which is NaOH.
We are given:

Putting values in above equation, we get:

The concentration of the phosphoric acid solution is 1.172 M
Answer:
The final volume is 1.6 L.
Explanation:
It is given that,
A diver has a lung capacity of 2.4 L when the pressure is 0.8 atm. We need to find the volume of the diver’s lungs when the pressure changes to 1.2 atm. Let V₂ is volume.
It is based on Boyle's law. According to this law,

K is constant


So, the final volume is 1.6 L.
Answer:
D. Solutions are formed when the water’s polar molecules separate the polar molecules of an ionic or molecular compound.
Explanation:
Solutions are homogeneous mixtures formed by interaction between solutes and solvents.
Water based solutions have water as the solvents and mostly ionic and molecular compounds as their solutes.
Water is a polar solvent that is capable of dissolving many compounds by hydrating them. The molecules of water surrounds the solute and forces them to separate.