Answer:
Explanation:
1) Given data:
Number of moles of lead = 4.3×10⁻³ mol
Mass of lead = ?
Solution:
Mass = number of moles × molar mass
Molar mass of lead = 207.2 g/mol
Mass = 4.3×10⁻³ mol × 207.2 g/mol
Mass = 890.96 g
2) Given data:
Number of atoms of antimony = 3.8×10²² atoms
Mass of antimony = ?
Solution:
1 mole contain 6.022 ×10²³ atoms
3.8×10²² atoms × 1 mol / 6.022 ×10²³ atoms
0.63×10⁻¹ mol
0.063 mol
Mass = number of moles × molar mass
Molar mass of lead = 121.76 g/mol
Mass = 0.063 mol × 121.76 g/mol
Mass = 7.67 g
3) Given data:
Mass of tungsten = 15.5 Kg (15.5 kg × 1000 g/ 1kg = 15500 g)
Number of atoms = ?
Solution:
Number of moles of tungsten:
Number of moles = mass/molar mass
Number of moles = 15500 g / 183.84 g/mol
Number of moles = 84.3 mol
1 mole contain 6.022 ×10²³ atoms
84.3 mol × 6.022 ×10²³ atoms / 1mol
507.65 ×10²³ atoms
Answer: a. Cathode
b. Galvanic cell
c. Anode
d. Electrolytic cell
e. half reaction
Explanation:
Galvanic cell or Electrochemical cell is defined as a device which is used for the conversion of the chemical energy produced in a spontaneous redox reaction into the electrical energy.
Electrolytic cell is a device where electrical energy is used to drive a non spontaneous chemical reaction.
In the electrochemical cell, the oxidation occurs at an anode which is a negative electrode and the reduction occurs at the cathode which is a positive electrode. Thus the electrons are produced at anode and travel towards cathode.
The balanced two-half reactions will be:
Oxidation half reaction : 
Reduction half reaction : 
Thus the overall reaction will be: 
Answer:
Mass of chlorine = 47.22 g
Explanation:
Given data:
Mass of sodium = 30.5 g
Mass of chlorine= ?
Solution:
Chemical equation:
2Na + Cl₂ → 2NaCl
Number of moles of Na:
Number of moles = mass/molar mass
Number of moles = 30.5g/ 23 g/mol
Number of moles = 1.33 mol
Now we will compare the moles of Cl
₂ with Na from balance chemical equation.
Na : Cl
₂
2 : 1
1.33 : 1/2×1.33 = 0.665 mol
Mass of chlorine gas:
Mass = number of moles × molar mass
Mass = 0.665 mol × 71 g/mol
Mass = 47.22 g
Explanation:
proton normally = atomic number
protons = 9
