Heat given out to the surroundings by the system = 225 J
Work done by the system on the surroundings = 645 J
According to the energy conservation, the energy can neither be created nor it can be destroyed, it can transform from one form to another. Hence, the energy which is lost to the surrounding as a work done and heat came from the internal energy of the system.
Hence, the change in the internal energy = - 225 - 645 = - 870 Joules
Negative sign means that the internal energy of the system is decreased by 870 Joules
Answer : It is a conclusion.
Explanation:
Conclusion: It is a judgement or decision which can be attained by reasoning.
From the observation table given we can conclude that :
- Aluminum ,bronze and steel took 27,45 and 80 seconds to melt small piece of wax respectively which means that more time will be required by them to transfer heat to the food while cooking. Hence, food will take more time to cook in them.
- Copper took less time of 15 seconds to melt the small piece of wax in comparison to other metal pots which means that it is a good conductor of heat in comparison to other. Hence, copper pot would be better for cooking food quickly.
After analyzing the observations and results in an experiment conclusion was made that copper pots are best for cooking foods.
Answer: The %w/w protein in the sample is 15.2 %
Explanation:
To calculate the number of moles for given molarity, we use the equation:
According to stoichiometry :
1 mole of 
require 1 mole of 
Thus 0.0023 moles of will require=
of
moles of HCl used = (0.0047-0.0023) = 0.0024
1 mole of HCl uses = 1 mole of ammonia
Thus 0.0024 moles uses = 
of ammonia
Mass of ammonia= 
17 g of ammonia contains = 14 g of Nitrogen
Thus 0.0408 g of ammonia contains = 
of Nitrogen
Now 17.45 g of Nitrogen is present in = 100 g of protein
Thus 0.034 g of Nitrogen is present in =
of protein
Now % w/w of protein = 
Thus %w/w protein in the sample is 15.2%
% yield = 80.719
<h3>Further explanation</h3>
Given
22.0 g of Mgl₂
25.0 g of Mg
25.0 g of l₂
Required
The percent yield
Solution
Reaction
Mg + I₂⇒ MgI₂
mol Mg = 25 g : 24.305 g/mol = 1.029
mol I₂ = 25 g : 253.809 g/mol = 0.098
Limiting reactant = I₂
Excess reactant = Mg
mol MgI₂ based on I₂, so mol MgI₂ = 0.098
Mass MgI₂ (theoretical):
= mol x MW
= 0.098 x 278.114
= 27.255 g
% yield = (actual/theoretical) x 100%
% yield = (22 / 27.255) x 100%
% yield = 80.719
equilibrium constant K = 4.15 × 10⁻³
Explanation:
We have the following chemical equilibrium:
2 SO₃ (g) ⇄ 2 SO₂ (g) + O₂ (g)
equilibrium constant K = ( [SO₂]² × [O₂] ) / [SO₃]²
equilibrium constant K = ( 0.00129² × 0.106 ) / 0.00652²
equilibrium constant K = 0.414 × 10⁻² = 4.14 × 10⁻³ ≈ 4.15 × 10⁻³
Learn more about:
equilibrium constant
brainly.com/question/2742049
brainly.com/question/7145687
#learnwithBrainly
