General Chemistry Answers

Metal x react with a non metal y wnd form a compound xy_2.mass percentage of x is 63.22%.determine the ratio of Relative atomic mass of x and y

A particular paint has a density of 0.914g/cm3. You need to cover a wall that is 7.6m long and 2.74m high with a paint layer 0.13mm thick. What volume of paint (in litres) is required? What is the mass (in grams) of the paint layer?

A gas mixture that has the following composition in percent by volume: 10.2% CO2, 2.3% CO,

18.5% H2, 21.0% C2H and 48.0% N2.

a) What is the density of this gas at 24 °C and 755 mmHg, in grams per litre?

b) What is the partial pressure of CO in this mixture at STP?

c), What volume of air is required for the complete combustion of this mixture of gas? (Air

contains 21% O2 by volume)

Lauric acid (C12/2402) is a typical fatty acid, a molecule with a long hydrocarbon chain and an

organic acid group (COOH) at the end. (a) Write a balanced equation for the complete

combustion of lauric acid to gaseous products. (b) Calculate AH°rxn for this combustion

(AH°+=-775.6 kJ/mol). (c) Calculate the heat (q) in kJ and kcal when 10.0 g of lauric acid is burned

completely. (AH° CO24g)=-393.5 kJ/mol, AH° $H20(g=-241.826 kJ/mol)

A sample of pure diamond was burned in pure oxygen, formed carbon dioxide was collected, and then bubbled through 3.50 L of 0.437 M sodium hydroxide solution. Bubbled carbon dioxide

was converted to sodium carbonate by the reaction shown below.

CO2(a) + NaOH,da) > Na) COgag) + H200)

After the reaction remaining, NaH was determined by back titration with 0.350 M HI solution,

and 1.71 L of the titrant was consumed for neutralization of the leftover NaH. What volume of

oxygen gas was consumed in the process if it was measured at 7.6 atm and 20 °C?

Calculate q, w, and AE for the vaporization of 25.0 g of liquid ethanol (C¿H; OH) at 1.00 atm

at 78.0 °C, to form gaseous ethanol at 1.00 atm at 78.0 °C. The density of liquid ethanol at 78.0

°C is 0.789 g/mL, and the heat of vaporization of ethanol is 855 J/g.

Sodium carbonate is a reagent that may be used to standardize acids in the same way you used 𝐾𝐻𝑃 in this experiment. In such a standardization, it was found that a 0.512 𝑔 sample of sodium carbonate required 26.30 𝑚𝐿 of a sulfuric acid solution to reach the end point for the reaction. 𝑁𝑎2𝐶𝑂3 (𝑎𝑞) + 𝐻2𝑆𝑂4 (𝑎𝑞) → 𝐻2𝑂 (𝑙) + 𝐶𝑂2 (𝑔) + 𝑁𝑎2𝑆𝑂4(𝑎𝑞) What is the molarity of the 𝐻2𝑆𝑂4? 

When 1.1.2g of iron reacts with 32g of bromine , iron (III)bromide is produced. Find the mass of iron (III) bromide.

Calculate the mass of ammonium phosphate in a 815mL, 0.163 mol/L sample of ammonium sulfate (NH4)2SO4(aq) solution.

Many people use a solution of trisodium phosphate, Na3PO4 to clean walls before putting up wallpaper. The recommended concentration is 1.7% (m/v). Calculate the molar concentration.