General Chemistry Answers

cobalt crystallizes in a HCP unit cell. it's atomic radius is 0.1253 nm. it's density is 8900 kg/m^3. using this information, estimate avogadro's number.

If 145g N2H4 and 175g of N2O4 are allowed to react N2H4 (1)+N2O4=N2(g)+H2O(1) datermine the limiting reactant,mass(in grams)of excess reactant and mass(in grams) of water

If 145g N2H4 and 175g N2O4 allowed to react N2H4+N2O4=N2+H2O

a hypothetical alloy has a face-centered cubic unit cell. its density is 10.470 kg/m^3, and its atomic weight is 106.8 g/molw. a. what is the atomic radius of the alloy in cm? b. what is the volume of the single atom of the alloy in cm^3?

What is K

sp

 for the following equilibrium if lithium phosphate has a molar solubility of 9.7×10

−4

 M

? 

Li

3

PO

4

(s)↽−

−⇀

3Li

+

(aq)+PO

3−

4

(aq)

• Your answer should have two significant figures.

Calculate the vapor pressure of a solution consisting of 5 moles of a nonvolatile solute and 23 moles of water at 25 °C, given that the vapor pressure of pure water at 25 °C is 22 mmHg.

Painting, oiling, galvanizing or tin-plating are methods of preventing rusting.

(a) Explain how these methods are similar in the way they prevent rusting

The vapor pressure of water at 25 °C is 23.8 mmHg. What is the vapor pressure of a solution containing 5.50 g of nonelectrolyte sucrose (MW_sucrose= 343 g/mol) in 12.8 g of water (MW_water= 18.0 g /mol) at 25.0 °C?

The vapor pressure of pure water at 85 °C is 434 torr. What is the vapor pressure at 85 °C of a solution prepared from 100 mL of water (density 1.00 g/mL) and 150 g of diglyme, C₆H₁₄O₃, a nonvolatile substance?

Potassium chromate, a bright yellow solid, is produced by the reaction of solid chromite ore (FeCr2O4)(FeCr2O4) with solid potassium carbonate and gaseous oxygen at high temperatures. In an experiment, 169000 g of chromite ore, 298000 g of potassium carbonate and 75000 g of oxygen are sealed in a reaction vessel and reacted at a high temperature. The amount of potassium chromate obtained was 194000 g. 

FeCr2O4 + K2CO3 + O2 -> K2CrO4 + Fe2O3 + CO2

Find the following:

1) limiting reactant

2) theoretical yield

3) percent yield

with solution if possible