Answer:
2.77 mL of boiling water is the minimum amount which will dissolve 500 mg of phthalic acid.
Explanation:
We know from the problem that 18 g of phthalic acid are dissolved in 100 mL of water at 99 °C.
Now we devise the following reasoning:
If 18 g of phthalic acid are dissolved in 100 mL of water at 99 °C
Then 0.5 g of phthalic acid are dissolved in X mL of water at 99 °C
X = (0.5 × 100) / 18 = 2.77 mL of water
Heterogeneous
The mixture has more than one phase of matter in it.
Atomic number is the number of protons in an atom and is equal to the number of electrons also.
Atomic number = 44.
Hence number of electrons in an atom of this element (with atomic number 44) = 44 electrons.
Answer:
b) 0.75 mol, 0.9375 mol
Explanation:
According to this question, ammonia reacts with oxygen to produce nitrogen monoxide and water. The chemical equation is as follows:
4NH3(g) + 5O2(g) → 4NO(g) + 6H2O(g)
Based on this balanced equation, 4 moles of ammonia (NH3) reacts with 5 moles of oxygen (O2).
A stoichiometric amount of the two reactants (NH3 and O2) must represent the ratio 4:5.
Given the provided options;
0.75 mol of ammonia (NH3) will react with (0.75 × 5/4) = 0.935 mol of O2 for them to be in stoichiometry.
N.B: 1 mol of NH3 will react with 1.25mol of O2 and not 1g, 1.25g.
