4Al + 3O₂ → 2Al₂O₃
m(Al)=54 g
M(Al)=27 g/mol
n(Al₂O₃)=n(Al)/2
n(Al)=m(Al)/M(Al)
n(Al₂O₃)=m(Al)/{2M(Al)}
n(Al₂O₃)=54/{2*27}= 1 mol
Na₂CO₃(s) → 2Na⁺(aq) + CO₃²⁻(aq)
The sodium carbonate formed from a strong base and a weak acid. Hydrolysis is subjected to the anion of a weak acid.
CO₃²⁻ + H₂O ⇄ HCO₃⁻ + OH⁻
HCO₃⁻ + H₂O ⇄ H₂CO₃ + OH⁻
pH>7 alkaline solution
2Na⁺ + CO₃²⁻ + 2H₂O ⇄ 2Na⁺ + 2OH⁻ + H₂CO₃
Answer:
Because it keeps track of all the elements
It increases
The attractive force between the nucleus and the electrons INCREASES if the proton number increases while the number of energy levels remains constant.
Explanation:
Remember that protons carry a positive charge while electrons carry a negative charges. Unlike charges attract while like charges repel. An increase in the number of protons increases the positive charge of the atomic nucleus. This means that the force of attraction on the electron cloud of the atom increases.
This is why the atomic radius of atoms decreases across a period (from left to right) as the mass number of the atoms increase (while the number of electron orbitals remains the same across the period).
Learn More:
For more on the atomic radius check out;
brainly.com/question/13126562
brainly.com/question/1604565
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Answer: 41 7/10
Explanation: The mark is on the seventh out of ten marks