How many grams of KBr is required to prepare 100 mL of
2.0 M KBr solution?

Can someone me out on this question for my national 5 chemistry homework

When 1.50g of ba is added to 100g of water in a container open tothe atmosphere, the reaction shown below occurs and the temperatureof the resulting solution rises from 22 degrees to 33.10 degrees.if the specific heat of the solution is 4.18j/(g*c), calculatedelta h for the reaction, as written.ba (s)+2h2o(l) yields ba(oh)2(aq)+h2

If a sample of nitrogen gas contains 6.0 x10^24 atoms of nitrogen then about how many moles of nitrogen gas are in the sample