Answer:
it keeps the heat in and the bugs and flys out
Explanation:
Answer is: the molar mass od sodium carbonate (Na₂CO₃) is 106.0 g/mol.
M(Na₂CO₃) = 2 · Ar(Na) + Ar(C) + 3 · Ar(O).
M(Na₂CO₃) = 2 · 23 + 12 + 3 · 16 · g/mol.
M(Na₂CO₃) = 46 + 12 + 48 · g/mol.
M(Na₂CO₃) = 106 g/mol; molar mass of sodium carbonate.
Ar is relative atomic mass (the ratio of the average mass of atoms of a chemical element to one unified atomic mass unit) of an element.
1: True
2: True
3: False
4: False
(Question 2 might not be true, not sure)
A change in the Earth's magnetic<span> field resulting in the </span>magnetic<span> north being aligned with the geographic south, and the </span>magnetic<span> south being aligned with the geographic north. Also called </span>geomagnetic reversal<span>.</span>
Answer:
4.48 - 6.48
Explanation:
A pH indicator works in a better way in a range of pH = pKa ± 1. That means we need to determine the pKa of the indicator propyl red to find the range over which it change its color. That is:
pKa = -log Ka
pKa = -log 3.3x10⁻⁶
pKa = 5.48
That means the range over propyl red will change from yellow to red or vice versa is:
4.48 - 6.48
