How much potassium nitrate (KNO3) would dissolve in 50 milliliters of water at 45ºC given that 55g of KNO3 is dissolved in 150mL of water at 45°C. A. 19.7g
B. 15.1g
C. 18.3g
D. 23.3g

When fat comes in contact with sodium hydroxide, it produces soap and glycerin. determine whether this is a physical change or a chemical change. explain your answer

Calculate the first and second velocities of the car with four washers attached to the pulley, using the formulas v1 = 0.25 m / t1 , and v2 = 0.25 m / (t2 – t1) where t1 and t2 are the average times the car took to reach the 0.25 and the 0.50 meter marks. record these velocities, to two decimal places, in table e.

What happens when the number of protons in an atom changes