The number of moles in a substance indicates the amount of the substance that contains the same number of particles as 12 g of the Carbon-12 isotope [or equivalent to 6.02 × 10²³] (which is used as a standard in the world of moles).
Now,
if 6.02 × 10²³ atoms are found in 1 mole ofsodium
then let 9.76 × 10¹² atoms are found in x
⇒ x = (9.76 × 10¹² ) ÷ (6.02 × 10²³)
= 1.619 × 10⁻¹¹ mol
Now, mass = moles × molar mass
∴ mass of Na = 1.619 × 10⁻¹¹ mol × 23 g/mol
= 3.72 × 10⁻¹⁰ g
Answer:
SO₄²⁻(aq) +Sn²⁺(aq) +4H⁺ → H₂SO₃(aq) + Sn⁴⁺(aq) + H₂O
Explanation:
At first calculate the oxidation state of that element which undergoes oxidation as well as reduction.
for SO₄²⁻ the oxidation state of sulphur is +6 and H₂SO₃ the oxidation state of sulphur is +4
So balance equation is
(Reduction) SO₄²⁻ + 4H⁺+ 2e⁻ → H₂SO₃ + H₂O.........................................(1)
(oxidation) Sn²⁺ → Sn⁴⁺ + 2e⁻ .............................................................(2)
Adding equation 1 & 2
we get
SO₄²⁻(aq) +Sn²⁺(aq) +4H⁺ → H₂SO₃(aq) + Sn⁴⁺(aq) + H₂O
The stored energy in the battery does not work anymore.
Substances can change state, usually when they are heated or cooled. For example, liquid water turns into steam when it is heated enough, and it turns into ice when it is cooled enough. ... The closeness, arrangement and motion of the particles in a substance change when it changes state.
Pressure varies in the atmosphere because air molecules are being pulled down towards the center of the earth-hope this helps!