Answer:
Percent yield = 90.9%
Explanation:
Given data:
Mass of CaCO₃ = 50.0 g
Mass of CO₂ produced = 20.0 g
Percent yield = ?
Solution:
Chemical equation:
CaCO₃ → CaO + CO₂
Number of moles of CaCO₃:
Number of moles = mass/molar mass
Number of moles = 50.0 g/ 100.1 g/mol
Number of moles = 0.5 mol
Now we will compare the moles of CO₂ with CaCO₃.
CaCO₃ : CO₂
1 : 1
0.5 : 0.5
Mass of CO₂: Theoretical yield
Mass = number of moles × molar mass
Mass = 0.5 mol × 44 g/mol
Mass = 22 g
Percent yield:
Percent yield = ( actual yield / theoretical yield ) × 100
Percent yield = (20.0 g/ 22.0 g) × 100
Percent yield = 0.909 × 100
Percent yield = 90.9%
Answer:
See explanation
Explanation:
The cold drink chiller is a cold substance which is inserted into a bottle of drink which contains warm liquid particles at a particular temperature.
Once the drink chiller is inserted, the liquid molecules around the drink chiller become cooler, denser and sink away from the drink chiller. Other warmer, less dense molecules of the liquid drink now replaces them around the drink chiller.
A convection current is thus set up for as long as the drink chiller is working.
Answer:
Explanation:
A solid, at a given temperature, has a definite volume
and shape which may be affected by changes in
temperature. Solids usually increase slightly in size
when heated (expansion) and usually
decrease in size if cooled (contraction).A liquid, at a given temperature, has a
fixed volume and will take up the shape of any
container into which it is poured. Like a solid, a
liquid’s volume is slightly affected by changes in
temperature.
A gas, at a given temperature, has neither a definite
shape nor a definite volume. It will take up the shape
of any container into which it is placed and will
spread out evenly within it. Unlike those of solids
and liquids, the volumes of gases are affected quite
markedly by changes in temperature.
Answer:
If the amount of magnification is correct, then an individual germ can be seen, because individual germs exist but are too small for human eyes.
Explanation:
<em>Leeuwenhoek was the first scientists to experiment with microorganisms using a self-designed single-lens microscope. He described the tiny organisms as 'animacules'. He is known for his pioneer work in the design of the first microscope.</em>
The microscope works by magnifying objects placed on the stage. Germs are microbes that cannot be seen with ordinary eye unless they are magnified appropriately. They are virtually everywhere, including the parts of the world where humans cannot survive.
Hence, the only correct option which most likely inspired Leeuwenhoek's experimentation with technology is the first option. The remaining options are deficient in some ways.
The opposite type of reaction (where energy is taken in from the surroundings of a reaction and thus the energy of the reactants is lower than that of the products) is called an endothermic reaction