First, we have to get the theoretical yield of CaO:
the balanced equation for the reaction is:
CaCO3(s)→CaO(s) +CO2(g)
covert mass to moles:
moles CaCO3 = mass of CaCO3 / molar mass of CaCO3
= 2x10^3 /100 = 20 moles
the molar ratio between CaCO3 : CaO = 1:1
∴moles of CaO = 1* 20 = 20 moles
∴mass of CaO = moles of CaO * molar mass of CaO
= 20 * 56 = 1120 g
∴the theoritical yield = 1120 g and we have the actual yield =1.05X10^3
∴Percent yield = actual yield / theoritical yield *100
= (1.05x10^3) / 1120 * 100
= 94 %
The reaction of Butanoic acid and excess ethanol occurs as shown in the equation;
CH₃CH₂CH₂COOH + CH₃CH₂OH = CH₃CH₂CH₂COOCH₂CH₃ + H₂O
1 mole of butanoic acid contains 88g/mol
Thus, 7.35 g of butanoic acid contains;
= 7.35/88
= 0.0835 moles
The mole ratio of butanoic acid and ethylbutyrate is 1:1
Thus moles of ethyl butyrate produced is 0.0835 moles
But 1 mole of ethyl butyrate contains 116 g/mol
Hence, the mass of ethyl butyrate will be
=0.0835 × 116
=9.686 g
<h3><u>Answer;</u></h3>
<em>All the above</em>
Workers at construction sites often reduce erosion by;
- <em>Moving excess sediment back to its original location
</em>
- <em>Planting trees
</em>
- <em>Spraying water on bare soil</em>
<h3><u>Explanation;</u></h3>
- Soil erosion is a naturally occurring process which involves the wearing away of the topsoil by natural forces such as wind, water or other forces associated with farming.
- <em><u>Construction of roads and buildings results to large amounts of soil erosion around the world. It is therefore important to put measures that would help reduce soil erosion at construction sites</u></em>. These measures uses principals of soil control such as implementing sediment control, limiting soil exposure, reducing the runoff velocity, and modifying topography among others.
Answer: The answer is D
Explanation:
So there is 2K + 2H2O --> 2KOH + 1H2
2Potassium + 2Water ---> 2Potassium Hydroxide + 1Dihyrogen
Initial temperature = -189.4 °C
<h3>Further explanation</h3>
Given
the volume of a gas is changed from 3.6 L to 15.5 L
final temperature = 87 °C = 87+ 273 = 360 K
Required
initial temperature
Solution
Charles's Law
<em>When the gas pressure is kept constant, the gas volume is proportional to the temperature </em>