Mass of CO₂ evolved : 0.108 g
<h3>Further explanation</h3>
Given
1.205g sample, 36% MgCO3 and 44% K2CO3
Required
mass of CO2
Solution
0.36 x 1.205 g=0.4338 g
mass C in MgCO₃(MW MgCO₃=84 g/mol, Ar C = 12/gmol)
= (12/84) x 0.4338
= 0.062 g
0.44 x 1.205 g = 0.5302 g
Mass C in K₂CO₃(MW=138 g/mol) :
= (12/138) x 0.5302
= 0.046 g
Total mass Of CO₂ :
= 0.062 + 0.046
= 0.108 g
Answer:
D. Strong nuclear force, electrostatic force, weak nuclear force, gravitational force
The answer is 67 108.0888km/s.
Answer:
b. The final state of the substance is a gas.
d. The sample is initially a liquid. One or more phase changes will occur.
Explanation:
Methane has the following properties:
- Normal melting point: 90.7 K
- Normal boiling point: 111.65 K
*"Normal" refers to normal pressure (1 atm).
According to this, we can affirm:
- Below 90.7 K, methane is solid.
- Between 90.7 K and 111.65 K, methane is liquid.
- Above 111.65 K, methane is gas.
<em>A sample of methane at a pressure of 1.00 atm and a temperature of 93.1 K is heated at constant pressure to a temperature of 158 K. Which of the following are true? Choose all that apply.</em>
<em>a. The liquid initially present will solidify.</em> FALSE. The liquid will vaporize.
<em>b. The final state of the substance is a gas.</em> TRUE.
<em>c. The sample is initially a solid.</em> FALSE. The sample is initially a liquid.
<em>d. The sample is initially a liquid. One or more phase changes will occur. </em>TRUE.
The empirical formula, <span>C<span>H2</span></span>, has a relative molecular mass of
<span>1×<span>(12.01)</span>+2×<span>(1.01)</span>=14.04</span>
This means that the empirical formula must be multiplied by a factor to bring up its molecular weight to 70. This factor can be calculated as the ratio of the relative masses of the molecular and empirical formulas
<span><span>7014.04</span>=4.98≈5</span>
Remember that subscripts in molecular formulas must be in whole numbers, hence the rounding-off. Finally, the molecular formula is
<span><span>C<span>1×5</span></span><span>H<span>2×5</span></span>=<span>C5</span><span>H<span>10</span></span></span>
