Answer:
1) d = 2.4 g/cm³
2) m = 25 g
3) v = 126.7 cm³
Explanation:
Given data:
Mass of material = 24 g
Volume of material = 10 cm³
Density of material = ?
Solution:
Formula:
d = m/v
by putting value,
d = 24 g / 10 cm³
d = 2.4 g/cm³
2) Given data:
Density of material = 5 g/cm³
Volume of material = 5 cm³
Mass of material = ?
Solution:
Formula:
d = m/v
5 g/cm³ = m / 5 cm³
m = 5 g/cm³×5 cm³
m = 25 g
3)Given data:
Density of material = 3 g/cm³
Mass of material = 380 g
Volume of material = ?
Solution:
Formula:
d = m/v
3 g/cm³ = 380 g / v
v = 380 g /3 g/cm³
v = 126.7 cm³
Answer : Option A) Atomic number of Arsenic is 33.
Explanation : Arsenic contains same number of protons in its atomic nucleus. In arsenic there are 33 protons found in the atomic nucleus. Hence, the atomic number will be 33. It has 5 valence electrons in its outermost shell, which is also called as valence shell. So, its valency becomes 5.
A chemical formula shows the kinds and numbers of <u>atoms</u> in the smallest representative unit of a substance.
<u>Explanation:</u>
In chemistry, a formula unit is the empirical formula of "ionic or covalent network solid compound" that is used as an independent entity for "stoichiometric calculations". This formula is a representation of a molecule that uses chemical symbols.
The unit is the lowest whole number ratio of ions represented in an ionic compound. It gives the numbers of atoms representing the "smallest representative" unit of a substance. The number of atoms also tells us about the chemical and physical properties of the compound formed.
As I understand from your question, we should synthesize nickel sulfate first from nickel (II) oxide and sulfuric acid and second from nickel carbonate and sulfuric acid.
The chemical reactions will look like this:
NiO (s) + H₂SO₄ (aq) → NiSO₄ (aq) + H₂O (l)
NiCO₃ (aq)* + H₂SO₄ → NiSO₄ (aq) + H₂CO₃ (aq)
but carbonic acid will decompose to carbon dioxide and water
H₂CO₃ (aq) → CO₂ (g) + H₂O (l)
(*) NiCO₃ has a poor solubility in water, but enough to start the reaction.
