Answer:
The mass of 10 cm³of a 0.4 g/dm³ solution of sodium carbonate is 0.004 grams
Explanation:
The question is with regards to density calculations
The density of the given sodium carbonate solution, ρ = 0.4 g/dm³
The volume of the given solution of sodium carbonate, V = 10 cm³ = 0.01 dm³
Therefore, we have;
The mass, "m", of the sodium carbonate in = ρ×V = 0.4 g/dm³ × 0.01 dm³ = 0.004 g
The mass of 10 cm³ (10 cm³ = 0.01 dm³) of a 0.4 g/dm³ solution of sodium carbonate, m = 0.004 g.
Percent composition by mass of oxygen =
((16.0*6)/(40.1+2*(14.0+16.0*3)))*100%
= 58.5%
therefore, the answer is D
Answer:
Explanation:
Glucose reacts with oxygen do produce carbon dioxide and water:
Given a daily mass of glucose:
Find moles of glucose:
From stoichiometry of this equation, moles of carbon dioxide can be found by multiplying this amount by 6:
Convert this into mass using the molar mass of carbon dioxide:
This is the mass of carbon dioxide per person per day. Multiply by the population and by the number of days to get the total mass:
