Physical Chemistry Answers

If 13.9g N_2_ and 1.89g H_2_ react to produce 1.45g NH_3_, what is the percent yield of the reaction?

N_2_ + 3H_2_ --> 2NH_3_

What is the amount of Neon atoms in 20.2g of Neon?
What is the number of oxygen molecules in 49.6g of oxygen gas?
What is the number of atoms of oxygen in 132g of carbon dioxide?
What is the number of chlorinde ions in 129.9g of iron (III) chloride?

tWhat is the second action to perform to resuscitate a victim of gas inhalation in the laboratory?

Calculate the change in temperature (ΔT) for each of the following using the table below:
Gold has a specific heat of .129 j/g C
Copper has specific heat of .385 j/g C


Solve:87.1 g of gold (Au) that absorbs 7620 J
52.9 g of copper (Cu) that absorbs 7.35 kJ

0.015 g moles of NH4OH and 0.025 g moles of NH4Cl are present in a solution then pH of mixture is :-

10 raised to the power -6 M HCl is diluted to 100 times. Its pH is?
(1) 6.0
(2) 8.0
(3) 6.95
(4) 9.5

The pH of a 10 raised to power -10 M NaOH solution is nearest to? and how?
(1) 10
(2) 7
(3) 4
(4) -10

How many moles of HCl must be removed from 1 litre of aqueous HCl solution to change it's pH from 2 to 3?

In a buffer solution the ratio of concentration of NH4Cl and NH4OH is 1:1 when it changes in 2:1 what will be the value of pH of buffer? and how?
(1) Increase
(2) Decrease
(3) No change