____ hold the wall forms together at the desired distance apart.

Which of the following is a correct Lewis Dot Structure for PF4 – ?

Automotive airbags inflate when sodium azide, NaN3, decomposes according to the following equation. Calculate the mass of sodiumazide that would be required to produce 354.0 g of N2 gas, which would fill a normal airbag. 2 NaN3 (s) → 2 Na (s) + 3 N2(g)

What is the enthalpy change, ∆H°, for the reaction shown below. Compound ∆H°f (kJ/mol) C2H2 (g) +226.7 CO2 (g) – 393.5 H2O (g) – 241.6 2 C2H2 (g) + 5 O2 (g) –> 4 CO2 (g) + 2 H2O (g)

If 0.883 g of N2 is released into an empty 4.68 L flask at 66.0°C, what would the pressure in the flask be?

Calcium hydroxide reacts with hydrochloric acid according to the equation shown below. If 31.25 mL of calcium hydroxide reacts with 42.58 mL of 0.362M HCl, what is the concentration of the calciumhydroxide? Ca(OH)2 (aq) + 2 HCl (aq) ––> CaCl2 (aq) + 2 H2O (l)

What is the strontium concentration when 16.4 g of SrCl2 is dissolved in enough water to make 275 mL of solution?

The ______ are the land snails and slugs. They’re adapted to living on land by having a thinner shell and a specialized gas exchange cavity formed by a modification of the mantle (hint – this last characteristic gives the group its name).

A test done on the job site to test the consistency of concrete is called a ____.

Calculate the frequency of light emitted from a hydrogen atom when an electron falls from the n=6 level to the n=3 level.