Answer:
(d) 4.5 M
Explanation:
We have 70.0 mL of 3.0-molar Na₂CO₃. The moles of Na₂CO₃ are:
70.0 × 10⁻³ L × 3.0 mol/L = 0.21 mol
There are 2 moles of Na⁺ in 1 mole of Na₂CO₃. The moles of Na⁺ in 0.21 moles of Na₂CO₃ are 2 × 0.21 mol = 0.42 mol
We have 30.0 mL of 1.0-molar NaHCO₃. The moles of NaHCO₃ are:
30.0 × 10⁻³ L × 1.0 mol/L = 0.030 mol
There is 1 mole of Na⁺ in 1 mole of NaHCO₃. The moes of Na⁺ in 0.030 moles of NaHCO₃ are 1 × 0.030 mol = 0.030 mol
The total number of moles of Na⁺ is 0.42 mol + 0.030 mol = 0.45 mol
The total volume is 70.0 mL + 30.0 mL = 100.0 mL
The concentration of Na⁺ is
0.45 mol / 0.1000 L = 4.5 M
Answer:
B and C
Explanation:
Selective breeding is a procedure that involves the purposeful breeding of selected parents in order to give rise to offsprings with desired traits. Selective breeding procedure has its own advantages, which includes the ability to produce more animal products such as milk, meat etc, however, it has disadvantages.
The disadvantages include that:
- Selectively bred animals are more likely to have some health problem
- Some desirable traits become more common in a population.
Electron gain enthalpy of the atom - if im not wrong