Answer:
False
Explanation:
Water molecules are spread up but slightly, enough that none of the molecules actually move freely around each other. Only gas and plasma molecules are very spread apart.
Answer: A
Explanation:
A Gold (Au) atom has 79 protons and 79 electrons. A typical gold atom has 118 neutrons, though there are 18 other radioisotopes discovered so far. 79 is its charge (atomic number), which is both its proton number and electron number
Explanation:
Upon dissolution of KCl heat is generated and temperature of the solution raises.
Therefore, heat generated by dissolving 0.25 moles of KCl will be as follows.

= 4.31 kJ
or, = 4310 J (as 1 kJ = 1000 J)
Mass of solution will be the sum of mass of water and mass of KCl.
Mass of Solution = mass of water + (no. of moles of KCl × molar mass)
= 200 g + 
= 200 g + 13.625 g
= 213.625 g
Relation between heat, mass and change in temperature is as follows.
Q = 
where, C = specific heat of water = 
Therefore, putting the given values into the above formula as follows.
Q = 
4310 J =
Thus, we can conclude that rise in temperature will be
.