A solution of HCl is 0.450 M. How many moles of hydrochloric acid (HCl) are dissolved in 250.0 mL of solution?

200. ml of 3.00 m nacl solution is diluted to a final volume of 500. ml. what is the molarity of the final solution?

Tin has ten stable isotopes. the heaviest, 124sn, makes up 5.80% of naturally occuring tin atoms. how many atoms of 124sn are present in 82.0 g of naturally occurring tin? what is the total mass of the 124sn atoms in this sample?

Agas can holds 2.0 gal of gasoline. what is this quantity in cubic centimeters?