In a balanced chemical equation, we have two numbers that indicate two different factors. The definitions of these numbers are as follows:
1- Molar ratio: This ratio represents the ratio between the number of moles of any two substances in the balanced equation
2- The coefficients in the balanced chemical equation: These numbers represent the numbers of particles of each of the substances taking place in this chemical equation.
D.
This is in accordance with the law of conservation of energy.
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Answer:</h3>
915 Joules
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Explanation:</h3>
- The heat of fusion is the heat that is required to convert a given mass of a substance from solid state to liquid state without change in temperature.
- In this case, we are given specific heat of a substance as 122 joules per gram
- It means that amount of heat equivalent to 122 joules is required to change 1 gram of the substance from solid state to liquid state.
- Therefore, we can determine the amount of heat needed to change 7.5 grams of the substance from solid to liquid state.
1 g = 122 Joules
7.5 g = ?
= 122 × 7.5
= 915 Joules
Thus, 7.5 g of the substance at its melting point will require 915 Joules of heat to melt.
Answer: 35.4 grams
Explanation:
Molarity of a solution is defined as the number of moles of solute dissolved per Liter of the solution.

where,
Molality = 2.65
n= moles of solute =?
= volume of solution in ml = 445 ml
Putting in the values we get:


Mass of solute in g=
Thus 35.4 grams of
is needed to prepare 445 ml of a 2.65 m solution of
.
yes
Explanation:
the molar mass of a compound is g/mol