Answer:
10.9%.
Explanation:
The first thing to do in order to solve this question is to Determine the value for the volume of the the cube. This can be done by taking the cube root of the length of the cube;
The volume of the cube = (length of the cube)^3 = length × length × length = 1.72 × 1.72 × 1.72 =( 1.72)^3 = 5.09cm^3.
The next thing you do is to Determine the exponential density, the can be done by using the formula below;
The exponential density = mass/ volume = 55. 786/ 5.09 = 10.96 g/cm^3.
Therefore, the percent error = (true density of the cube - exponential density of the cube)÷ true density of the cube × 100.
Hence, the percent error = 12.30 - 10.96/12.30 × 100 = 10.9%.
Answer:
Option C.
2 Mg (s) + O₂(g) → 2MgO (s)
Explanation:
Two moles of magnesium solid react with one mol of oxygen gas to
form two moles of magnesium-oxide solid
2 Mg (s) + O₂(g) → 2MgO (s)
That's the reaction for the magnessium oxide's formation.
Be careful cause we do not say molecules, they are moles.
The stoichiometry indicates the number of moles that react and the moles which are produced.
It is a redox reaction, because the magnessium is oxidized and the oxygen is reduced. Both elements, changed the oxidation states.
The fomula is NH4 (1+)
There are only two elements N and H.
As per oxidation state rules, the most electronegative element will have a negative oxidation state and the other element will have a positive oxidation state.
N is more electronative than H, so H will have a positive oxidation state and nitrogen will have a negative oxidation state.
You can also use the rule that states the hydrogen mostly has 1+ oxidation state,except when it is bonded to metals.
In conclusion the oxidation state of H in NH4 (1+) is 1+.
Now you must know that the sum of the oxidations states equals the charge of the ion, which in this case is 1+.
That implies that 4* (1+) + x = 1+
=> x = (1+) - 4(+) = 3-
Answer: the oxidation state of N is 3-, that is the option b.
A caption is a positively charged ion. They are formed when an ion loses one or more electrons. Typical it is the loss Of their valence electrons.
