SI units are the modern form of?

A 650.0 g hard-water sample contains 101 mg Ca. what is this concentration in parts per million

How many valence electrons does a neutral fluorine atom have? a. 1 b. 7 c. 8 d. 9

The average density of a carbon-fiber-epoxy composite is 1.615 g/cm3. the density of the epoxy resin is 1.21 g/cm3 and that of the carbon fibers is 1.74 g/cm3.

Determine the theoretical yield of HCl if 60.0 g of BCl3 and 37.5 g of H2O are reacted according to the following balanced reaction. A possibly useful molar mass is BCl3 = 117.16 g/mol. BCl3 (g) + 3 H2O (l) → H3BO3 (s) + 3 HCl (g)

Be sure to answer all parts. Enter the formula for potassium dihydrogen phosphate and determine its molecular (formula) mass.

A balloon contains 1.00 mol helium gas at STP. What will the volume of the balloon be if the pressure increases to 2.00 atm?

If 100 mL of a gas were enclosed in a buret at 500 mm Hg, what volume would the gas occupy at 1000 mm Hg at the same temperature? P1V1=P2V2

Would Mn (HPO4) 2 be manganese (II) monohydrogen phosphate?

The fundamental frequency of a violin string is 440 hz. the frequency of its second harmonic is

How much of a 15.0M stock solution do you need to prepare 250ml of a 2.35ml hf solution?