2 stands for valency of ca ion
its +2
that it takes two electrons to complete its shell
1.38 moles of oxygen
Explanation:
Thermal decomposition of Lead (II) nitrate is shown by the balanced equation below;
2Pb(NO₃)₂ → 2PbO + 4NO₂ + O₂
The mole ration of Lead (II) nitrate to oxygen is 2: 1
Therefore 2.76 moles of Lead (II) nitrate will lead to production of? moles of oxygen;
2: 1
2.76: x
Cross-multiply;
2x = 2.76 * 1
x = 2.76 / 2
x = 1.38
Covalent and hydrogen bonds
Answer:
is the total displacement (volume) of the submarine.
Explanation:
Mass of water carried by submarine at 1000 ft depth = m = 2100 kg
The density of seawater at 1000 ft depth = d = 
Volume of the water displaced = V= ?
Total displacement of the submarine = Volume of the water displaced = V


is the total displacement (volume) of the submarine.
Answer:

Explanation:
The Rydberg equation gives the wavelength λ for the transitions:

where
R= the Rydberg constant (1.0974 ×10⁷ m⁻¹) and

Data:

λ = 657 nm
Calculation:
