The balanced equation given is:
4NH3 + 3O2 .....> 2N2 + 6H2O
From this equation, we can note that 4 moles of NH3 are required to produce 2 moles of N2.
Therefore, the mole ratio of NH3 to N2 is 4:2 which can be simplified into 2:1
The first step is to calculate the molarity of each compound:
final volume of solution = 157 + 139 = 296 mL
molarity of <span>nac2h3o2 = (157 x 0.35) / 296 = 0.1856 molar
molarity of </span><span>hc2h3o2 = (139 x 0.46) / 296 = 0.216 molar
Then, we calculate the pH as follows:
pKa of acetic acid = -log(</span><span>1.75 × 10^-5) = 4.7569
pH = pKa + </span><span> log ([salt] / [acid])
= </span>4.7569 + log(0.1856 / 0.216)
= 4.691
Hey there!
Molar mass N2 = 28.01 g/mol
Therefore:
28.01 g N2 -------------- 6.02*10²² molecules N2
( mass N2 ?? ) ----------- 25,000 molecules N2
mass N2 = ( 25,000 * 28.01 ) / ( 6.02*10²³ )
mass N2 = 700250 / 6.02*10²³
mass N2 = 1.163*10⁻¹⁸ g
Hope that helps!
We have to know the number of Na⁺ ions in the unit cell.
The number of Na⁺ ions in the unit cell is (D) 8.
Sodium oxide (Na2O) crystallizes in a structure in which the O2– ions are in a face - centered cubic lattice and the Na+ ions are in tetrahedral holes.
O²⁻ ions are in a face centred cubic lattice, so the number of O²⁻ ions per unit cell is equal to 4. The number of tetrahedral hole= 2 X 4=8. Na+ ions are present in tetrahedral holes, which indicates there are 8 number of Na+ ions in the unit cell.
Question 1 the answer is sheng
Question 2 is Zheng
Question 3 is B
