Answer:
M.Mass = 3.66 g/mol
Data Given:
M.Mass = M = ??
Density = d = 0.1633 g/L
Temperature = T = 273.15 K (Standard)
Pressure = P = 1 atm (standard)
Solution:
Let us suppose that the gas is an ideal gas. Therefore, we will apply Ideal Gas equation i.e.
P V = n R T ---- (1)
Also, we know that;
Moles = n = mass / M.Mass
Or, n = m / M
Substituting n in Eq. 1.
P V = m/M R T --- (2)
Rearranging Eq.2 i.e.
P M = m/V R T --- (3)
As,
Mass / Volume = m/V = Density = d
So, Eq. 3 can be written as,
P M = d R T
Solving for M.Mass i.e.
M = d R T / P
Putting values,
M = 0.1633 g/L × 0.08205 L.atm.K⁻¹.mol⁻¹ × 273.15 K / 1 atm
M = 3.66 g/mol
Answer: 1. magnesium hydroxide + sulfuric acid = magnesium sulphate + water
2. calcium hydroxide + hydrochloric acid = calcium chloride + water
3. lead hydroxide + nitric acid = lead nitrate + water
4. sodium hydroxide + sulfuric acid = sodium sulphate + water
5. potassium hydroxide + citric acid = potassium citrate + water
6. silver hydroxide + hydrochloric acid = silver chloride + water
7. aluminium hydroxide + phosphoric acid = aluminium phosphate + water
Explanation:
A double displacement reaction is one in which exchange of ions take place. The salts which are soluble in water are designated by symbol (aq) and those which are insoluble in water and remain in solid form are represented by (s) after their chemical formulas.
The balanced chemical equations are :
1. magnesium hydroxide + sulfuric acid = magnesium sulphate + water

2. calcium hydroxide + hydrochloric acid = calcium chloride + water

3. lead hydroxide + nitric acid = lead nitrate + water

4. sodium hydroxide + sulfuric acid = sodium sulphate + water

5. potassium hydroxide + citric acid = potassium citrate + water

6. silver hydroxide + hydrochloric acid = silver chloride + water

7. aluminium hydroxide + phosphoric acid = aluminium phosphate + water

Answer : The correct option is, (D) CO₂, BCl₃, and Fe³⁺
Explanation :
According to the Lewis concept, an acid is defined as a substance that accepts electron pairs and base is defined as a substance which donates electron pairs.
(a) 
It is a Lewis-acid because it can accepts electron pairs.
(b) 
It is not a Lewis-acid because it can not accepts electron pairs but it is a base because it can donates and accept hydrogen ion.
(c) 
It is a Lewis-acid because it can accepts electron pairs because it has an incomplete octet and an empty 2p orbital.
(d) 
It is a Lewis-acid because it can accepts electron pairs.
Hence, the ions which behave as Lewis acids are, CO₂, BCl₃, and Fe³⁺
Answer:
4
Explanation:
The balanced equation for the reaction is as follows:
4Al + 3O2 --> 2(Al2O3)
Answer:
Dmitri Mendeleev
used patterns to predict undiscovered
elements
Johann Wolfgang Dobereiner
created groups of three elements,
each based on similar properties
John Newlands
arranged elements according to their
atomic mass
Antoine Lavoisier,
divided elements into four categories
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