The thing you MUST do FIRST is look for any H's, O's, or F's in the equation
1)any element just by itself not in a compound, their oxidation number is 0
ex: H2's oxidation number is 0
ex: Ag: oxidation number is 0 if its just something like Ag + BLA = LALA
2) the oxidation number of H is always +1, unless its just by itself (see #1)
3) the oxidation number of O is always -2, unless its just by itself (see #1)
4) the oxidation number of F is always -1, unless its just by itself (see#1)
ok so after you have written those oxidation numbers in rules 1-4 over each H, F, or O atom in the compound, you can look at the elements that we havent talked about yet
for example::::
N2O4
the oxidation number of O is -2.
since there are 4 O's, the charge is -8. now remember that N2O4 has to be neutral so the N2 must have a charge of +8
+8 divided by 2 = +4
N has an oxidation number of +4.
more rules:
5) the sum of oxidation numbers in a compound add up to 0 (when multiplied by the subscripts!!!) (see above example)
6) the sum of oxidation numbers in a polyatomic ion is the charge (for example, PO4 has a charge of (-3) so
oxidation # of O = -2. (there are 4 O's = -8 charge on that side ) P must have an oxidation number of 5. (-8+5= -3), and -3 is the total charge of the polyatomic ion
Answer:
Do not use this exact photo please!
Explanation:
Answer:
A) 0.801
Explanation:
The reaction that takes place is:
- 2NaOH + H₂SO₄ → Na₂SO₄ + 2H₂O
First we c<u>alculate the H₂SO₄ moles that reacted</u>:
- 0.355 M * 28.2 mL = 10.011 mmol H₂SO₄
Now we <u>convert H₂SO₄ moles to NaOH moles</u>:
- 10.011 mmol H₂SO₄ *
= 20.022 mmol NaOH
Finally we <u>calculate the molarity of the NaOH solution</u>:
- 20.022 mmol NaOH / 25.0 mL = 0.801 M
So the answer is option A.
Answer: (3) carbon dioxide
Explanation: Solubility of solids and liquids is not affected by pressure as they are highly incompressible. Methanol is liquid, carbon dioxide is a gas, sugar is a solid and sodium nitrate is also a solid.
But solubility of gases is affected by pressure as they are compressible and the solubility is governed by Henry's law, which states that mass of gas dissolved in a given liquid ta constant temperature is directly proportional to the pressure of the gas present in equilibrium with the liquid.
Increase in pressure increases the solubility as increase in pressure would lead to decrease in volume of gas particles and hence more number of particles will be present per unit volume and as a result, the number of particles striking the surface of solution and entering the solution will increase. Thus solubility increases.
