The answer is 2.0, and it is because
We balance the given reactions above by following the rules in balancing redox reactions in acidic or basic solutions. Balance the atoms aside from the O and H atoms. Then we balance the Os and Hs by adding H2O or H+. Finally, we balance the total charge of the reactant and product by adding e-. We do as follows:
<span>A) H2O2 + Fe 2+ ---> Fe 3+ + H2O (in the acidic solution)
</span><span> 2H+ + </span>H2O2 + Fe 2+ ---> Fe 3+ + 2H2O
e- + 2H+ + H2O2 + Fe 2+ ---> Fe 3+ + 2H2O
<span>
C) CN- + MnO4- ---> CNO- +MnO2 (in basic solution)
</span> CN- + MnO4- ---> CNO- +MnO2 + H2O
2H+ + CN- + MnO4- ---> CNO- +MnO2 + H2O
2OH- + 2H+ + CN- + MnO4- ---> CNO- +MnO2 + H2O + 2OH-
2H2O + CN- + MnO4- ---> CNO- +MnO2 + H2O + 2OH-
e- + H2O + CN- + MnO4- ---> CNO- +MnO2 + 2OH-
<span>
E) S2O2/3- + I2 ---> I- + S4O2/6- (in acidic solution)
2</span>S2O2/3- + I2 ---> 2I- + S4O2/6-
4H+ + 2S2O2/3- + I2 ---> 2I- + S4O2/6- + 2H2O
6e- + 4H+ + 2S2O2/3- + I2 ---> 2I- + S4O2/6- + 2H2O
The symbol of an isotope is:

A - the mass number
Z - the atomic number
X - the symbol of an element
The symbol of oxygen is O.
The atomic number is the same for all isotopes of one element. For oxygen it's 8, because every atom of oxygen has 8 protons in its nucleus.
The mass number is the number of nucleons (protons + neutrons) in the nucleus of an atom, and it's given in the name of an isotope. Oxygen-16 has the mass number 16, oxygen-17 has the mass number 17, oxygen-18 has the mass number 18.
Oxygen-16:

Oxygen-17:

Oxygen-18:
Answer:
Explanation:
Calcium carbonate decomposes at high temperatures to give calcium oxide and carbon
dioxide as shown below.
CaCO3(s) = CaO(s) + CO2(g)
The Kp for this reaction is 1.16 at 800°C. A 5.00 L vessel containing 10.0 g of CaCO3(s)
was evacuated to remove the air, sealed, and then heated to 800°C. Ignoring the volume
occupied by the solid, what will overall mass percent of carbon in the solid once equilibrium is reached?
Answer:
0.5ppm
Explanation:
Step 1:
Data obtained from the question.
Volume of water = 2500L
Mas of Cu = 1.25 g
Step 2:
Determination of the concentration of Cu in g/L. This is illustrated below:
Volume of water = 2500L
Mas of Cu = 1.25 g
Conc. of Cu In g/L =?
Conc. g/L = Mass /volume
Conc. of Cu in g/L = 1.25/2500
Conc. of Cu in g/L = 5x10^–4 g/L
Step 3:
Conversion of the concentration of Cu in g/L to ppm. This is illustrated below
Recall:
1g/L = 1000mg/L
Therefore, 5x10^–4 g/L = 5x10^–4 x 1000 = 0.5mg/L
Now, we know that 1mg/L is equal to 1ppm.
Therefore, 0.5mg/L is equivalent to 0.5ppm