What is the collection of protons and neutrons in the center of an atom called

Calculate the molarity of the solution: 6.02x10^22 molecules of HCl (molecular weight = 36.5 g/mole) in 2.0 liters of water.

Arsenic and silicon are similar in that they both

The modern periodic table is different from Mendeleevs in several ways. In which way are the two tables the same?

Draw the condensed structural formula for the ammonium salt formed when lidocaine reacts with hcl.

Calcium hydride reacts with water to form calcium hydroxide (aqueous) and hydrogen gas. part a write a balanced chemical equation for the reaction.

An equilibrium is dynamic. True False

In a lab, a student dissolves 6.9 g of sodium chloride (NaCl) in 125 g of water (H2O). What is the molality concentration of the solution?

Audrey is driving 50 miles in 2 hours what is her average speed?

Water has a specific heat of 4184 J / (kgK) how much energy is needed to increase the temperature os a kilogram of water 5C?

A student noticed while doing the neutralization experiment that the calorimeter kept getting warmer. how would this error affect the final calculation for the δhneut of each reaction? would it be overestimated, underestimated or remain unaffected?