The molar mass of Na₂SO₄ -
2 x Na - 2 x23 = 46
1 x S - 1 x 32 = 32
4 x O - 4 x 16 = 64
total = 46 + 32 + 64 = 142 g/mol
the molarity of solution - 2.0 M
in 1 L of solution , 2.0 moles
Therefore in 2.5 L - 2 mol/L x 2.5 L = 5 mol
then the mass of Na₂SO₄ required = 142 g/mol x 5 mol = 710 g
Answer:
HCl
Explanation:
Given data:
Mass of Zn = 50 g
Mass of HCl = 50 g
Limiting reactant = ?
Solution:
Chemical equation:
Zn + 2HCl → ZnCl₂ + H₂
Number of moles of Zn:
Number of moles = mass / molar mass
Number of moles = 50 g/ 65.38 g/mol
Number of moles = 0.76 mol
Number of moles of HCl:
Number of moles = mass / molar mass
Number of moles = 50 g/ 36.5 g/mol
Number of moles = 1.4 mol
Now we will compare the moles of Reactant with product.
Zn : ZnCl₂
1 : 1
0.76 : 0.76
Zn : H₂
1 : 1
0.76 : 0.76
HCl : ZnCl₂
2 : 1
1.4 : 1/2×1.4 = 0.7
HCl : H₂
2 : 1
1.4 : 1/2×1.4 = 0.7
Less number of moles of product are formed by HCl it will act limiting reactant.
Answer:
Option B. is correct
Explanation:
Wind turbines collect the kinetic energy of wind using the turbine blades. The blades turn an electric generator as they are connected to a drive shaft, which in turn produces electricity.
These turbine blades can disrupt flying wildlife including bats and birds.
So,
wind farms can disrupt migrating wildlife.
Option B. is correct.
To find the number of atoms in the sample of copper, we need its atomic mass and the use of the Avogadro's number to find the equivalent units in terms of atoms.
68.7 g Cu ( 1 mol / 63.55 g ) ( 6.022 x 10^23 atoms / 1 mol ) = 6.51 x 10^23 atoms Cu
