Answer is: Zn + Cu2+ → Zn2+ + Cu.
In this chemical reaction, there is transfer of electrons from zinc (Zn) to copper (Cu). Zinc change oxidation number from 0 to +2 (lost electrons) and copper change oxidation number from +2 to 0 (gain electrons).
Oxidation half reaction: Zn⁰ → Zn²⁺ + 2e⁻.
Reduction half reaction: Cu²⁺ + 2e⁻ → Cu⁰.
In other chemical reactions, there is no change of oxidation number of elements.
In this question, you are given the NaOH volume but asked for concentration.
Don't forget that for every 1 mol of NaOH there will be 1 mol OH- ion, but for every 1 mol of H2SO4 there will be 2 mol of H- ion.
To neutralize you need the same amount of OH- and H+, so the equation should be:
OH-= H+
<span>35.50cm3 * x*1= 25cm3* 0.2mol/dm3 *2
</span>x= 10/35.5 mol/dm3= 0.2816/dm3
Answer:
the attractive forces keep the particles together tightly enough so that the particles do not move past each other.
Explanation:
In the solid the particles vibrate in place.
<h3>
Answer:</h3>
12 years
<h3>
Explanation:</h3>
We are given;
Half life of hydrogen-3 is 12 years
Initial mass of Hydrogen-3 is 20 grams
Final mass will be 10 g because we are told half of the sample will decay.
To find the time taken for the decay we need to know what half life is;
- Half life is the time taken for a radioactive isotope to decay to half its original amount.
Remaining mass = Original mass × 0.5^n
n = number of half lives
therefore;
10 g = 20 g × 0.5^n
0.5 = 0.5^n
n = log 0.5 ÷ log 0.5
= 1
But, 1 half life is 12 years
Therefore, the time taken is 12 years
