Answer:
gaseous CO2 bubbles out of the solution
Explanation:
We already know that the dissolution of a gas in water is exothermic. Hence, when the temperature of a solution containing a gas is increased, the solubility of the gas decreases and the gas bubbles out of the solution.
Similarly, the dissolution of KNO3 in water is endothermic. This implies that the solubility of the solid increases with increasing temperature.
Thus the solid becomes more soluble at 75°.
In order to find the mass of tin with the given volume of 5.5 L and density of 7.265, we will use the formula
Density = Mass / Volume
We will just multiply both sides of the equation by the volume and we will get:
Mass = Volume x Density
We can now solve the problem by substituting the given.
Mass = 5.5 L x 7.265 g/L
Mass = 39.96 g
Answer: there are 39.96 grams of tin
Answer: The nuclide symbol of X is 
Explanation:
The given nuclear reaction is a type of alpha decay process. In this process, the nucleus decays by releasing an alpha particle. The mass number of the nucleus is reduced by 4 units and atomic number is also decreased by 2 units. The particle released is a helium nucleus.
The general equation representing alpha decay process is:

For the given equation :

As the atomic number and mass number must be equal on both sides of the nuclear equation:

Thus the nuclide symbol of X is 
Answer: The beaker in which water level has decreased more is the one that contains pure water.
Explanation: Even when water is not heated it can evaporate, that is because molecules move at different speed and those that are closer to surface can break the gass pressure and scape as water vapor.
The movement of molecules of water can be affected by the presence of solutes (salts or other soluble compounds) and increase the evaporation temperature. For this particular case, molecules of salt atract the water molecules (remember salt has ions and water is a dipole with partial charges) and do not let the water move freely which avoid them to scape to the surface.