Answer:
0.02 M
Explanation:
Given data:
Mass of sodium carbonate = 1.8 g
Volume of water = 862 cm³ (862/1000 = 0.862 L)
Concentration = ?
Solution:
Formula:
Concentration = number of moles / volume in L
Number of moles of sodium carbonate:
Number of moles = mass/molar mass
Number of moles = 1.8 g/ 106 g/mol
Number of moles = 0.02 mol
Concentration:
c = 0.02 mol / 0.862 L
c = 0.02 M
Answer:9.49g/mL
Explanation:
Mass of toy = 43.672g
Volume of water = 34.4mL
Volume of toy + volume of water = 39mL
Volume of toy = 39 — 34.4 = 4.6mL
Density = Mass /volume
Density = 43.672/4.6 = 9.49g/mL
<span>The coorrect answer is option A. The pressure of the gas can cause the ideal gas constant R, to take dfferent values. Because all the other three factors namely, Temperature (T), Volume(V) and the number of moles (n) can change the pressure of a gas. So, I f we change the pressure of the gas alone, we can change its gas constant R value.</span>
Answer:
The mass of water produced is 4.29 g.
Explanation:
Given;
reacting mass of ethane, C₂H₆ = 2.5 g
reacting mass of oxygen, O₂ = 5.0 g
The balanced combustion reaction is given as follows;
2C₂H₆ + 7O₂ ----------------> 4CO₂ + 6H₂O
Based on the balanced equation above;
requires
7.0 moles of oxygen -----------------------> 2.0 moles of ethane
requires
5.0 g of oxygen --------------------------> x gram of ethane
x = (2 x 5) / 7
x = 1.43 g
Ethane is in excess of 1.07g (2.5 g - 1.43g)
Now, determine the mass of water produced by 1.43 g of ethane;
requires
2.0 moles of ethane -----------------------> 6.0 moles of water
requires
1.43 g of ethane --------------------------> y gram of water
y = (6 x 1.43) / 2
y = 4.29 g
Therefore, the mass of water produced is 4.29 g.