Answer:
532 moles of O atoms.
Explanation:
Given data:
Number of moles of oxygen atom present = ?
Number of molecules of N₂O₅= 6.41×10²⁵ molecules
Solution:
First of all we will calculate the number of moles of N₂O₅.
1 mole = 6.022×10²³ molecules
6.41×10²⁵ molecules × 1 mol /6.022×10²³ molecules
106.4 mol
Number of atoms of O:
1 mole of N₂O₅ contain 5 moles of O atoms.
106.4×5 = 532 mol
Answer:
The answer to your question is letter D
Explanation:
Data
mass of Li = 4.5 g
mass of N₂ = 4.5 g
limiting reactant = ?
Reaction
6Li (s) + N₂ (g) ⇒ 2Li₃N
This reaction is balanced
Process
1.- Calculate the molecular mass of the reactants
Li = 7 x 6 = 42g
N = 14 x 2 = 28 g
Calculate the limiting reactant using proportions
Theoretical proportion Li / N = 42 / 28 = 1.5
Experimental proportion Li/N = 4.5/4.5 = 1
As the experimental proportion was lower than the theoretical, the limiting reactant is Lithium
2.- Calculate the theoretical yield of Li₃N
42 g of lithium -------------- 70 g of Li₃N
4.5 g of lithium ------------- x
x = (4.5 x 70) / 42
x = 315 / 42
<u> x = 7.5 %</u>
Answer: -
Rimmed steel does not contain nickel.
Explanation: -
Rimmed steel is a deoxidised low carbon steel. Deoxidation leads to formation of rims in the iron.
Carbon, sulfur and phosphorus is present in rimmed steel. The concentrations of these vary from the outer rim to the inner rim. It is not as tough as other steel.
Hence it is primarily used for products where a lot of bending is required. Thus Rimmed steel does not contain nickel.
Answer:
Explanation:
1) Find number of each of the type of atom that is present in the compound, using the chemical formula .
2) Then multiply number of atoms of each element that is present in the compound with the atomic weight of each of the element
3) Add everything together and add the units (grams/mole ) after the number
Let finds that of water
Chemical formula of water is (H20 )
hydogens atoms= 2
oxygen atom= 1
Atomic weight for Hydrogen= 1
Atomic weight for Oxygen= 16
Total number of atoms of Hydrogen from the formula (H2O)= 2
Total number of atoms of Oxygen from the formula (H2O)= 1
the molar mass=
Hydrogen: ( 2 x 1)= 2
Oxygen: ( 1 x 16)= 16
Add together= (16+2)
= 18
Then add the unit, we have(18 g/mol.)