D
Avogadro's number allows us to measure the amount of atoms or molecules in one mole of a substance.
A: 6.37gNaCl
B: 1 mol NaCl
C: 58.5 g NaCl
These answers are correct on e2020 I just got them right.
Answer:
Concentration of sulfuric acid in the acid rain sample is 0.0034467 mol/L.
Explanation:
Volume of NaOH = 1.7 ml = 0.0017 L
Molarity of NaOH = 0.0811 M
Moles of NaOH = n
n = 0.0001378 mol

According to reaction, 2 mol of NaOH neutralize 1 mol of sulfuric acid.
Then 0.0001378 mol of NaOH will neutralize:
of sulfuric acid.
Concentration of sulfuric acid in the acid rain sample: x

Concentration of sulfuric acid in the acid rain sample is 0.0034467 mol/L.
The number of Ml of a 0.40 %w/v solution of ,nalorphine that must be injected to obtain a dose of 1.5 mg is calculated as below
since M/v% is mass of solute in grams per 100 ml
convert Mg to g
1 g = 1000 mg what about 1.5 mg =? grams
= 1.5 /1000 = 0.0015 grams
volume is therefore = 100 ( mass/ M/v%)
= 100 x( 0.0015/ 0.4) = 0.375 ML
Answer:
he amount of heat gained by the water is 1.59 kJ
Explanation:
Relation between heat energy, specific heat and temperature change is as follows
Q = mCΔT
where, Q or q = heat energy
m = mass
C = specific heat =4.186J/g°C
ΔT = (28°C - 25°C) = 3°C
Now, putting the given values into the above formula as follows.
Q = mCΔT
= 127 × 4.186 × 3
= 1594.86 J or 1.59 kJ
Therefore, we can conclude that the amount of heat gained by the water is 1.59 kJ