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A chemist prepares an aqueous solution of sodium hydroxide.  The solution contains 263.3 g of NaOH and has a volume of 750.0mL.  What is the molarity (moles/liter) of this solution? M=mols/L Answer with correct unit (1 point) and correct significant figures ( 1 point) All work must be shown for credit. No work=no credit. All work must in your own hand-writing.  

In this reaction, what volume of nitrogen gas can be produced by the reaction of 25.0 g of NaN3, if the temperature is 350 K and the pressure is 1.2 atmospheres? The formula mass of NaN3 = 65 g/mol. R= 0.08206 L*atm / K*mol

An atom has atomic number 92 and mass number 238.  Which of these is an isotope of this ato  

Consider the following equation.  2 H2 (g) + O2 (g)  –> 2 H2O (g)   If 3.0 moles of H2 (g) react fully with oxygen how many moles of water will be made?

A 25.0 mL sample of HBr is neutralized by reaction with 20.0 mL of 3.00 M KOH.  What is the concentration of HBr is the unknown sample? *hint- find the concentration of the base first.

.  Based on electronegativities, a P-Cl bond is:

A sample of metal has a mass of [m] grams.  What is this mass in milligrams?

A solution has a mass of [x] grams, and a volume of [y] mL.  What is the density (g/mL) of this solution, reported to the correct number of significant digits?

An aqueous solution is found to have an H+ concentration of 7.8 x 10-2 M.  What is the concentration of OH- in this solution?

The following reaction is an example of an ___ reaction. 2 N2(g) + O2(g) → 2 N2O (g)             ΔHrxn = +163.2 kJ