B will make little difference to reaction rate while C and D will reduce the reaction rate. So the answer is A. adding heat energy to the reactants
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Answer:- Mass of the alloy is 2.8 kg.
Solution:- Mass of Cr in the alloy is 325 g and mass of Fe in the alloy is 2.5 kg. Mass of alloy would be the sum of masses of constituent metals.
Masses of the metals are not in the same units. So, we need to make the units equal. The want answer in kg so let's convert mass of Cr from g to kg.
Since, 1000 g = 1 kg
So, 
= 0.325 kg
Mass of alloy = mass of Cr + mass of Fe
mass of alloy = 0.325 kg + 2.5 kg = 2.825 kg
If we consider significant figures then as per the rules, the answer should not have more than one decimal place.
So, 2.825 kg is round off to 2.8 kg and hence the mass of the alloy is 2.8 kg.
13% of 0.900 is 0.117
there are 0.117 milliliters of alcohol in a 0.900-L bottle of wine.
If 5.0 grams of KCl is dissolved in 500 ml of water, the concentration of the resulting solution will be 0.134M.
<h3>How to calculate concentration?</h3>
The concentration of a solution can be calculated by using the following formula;
Molarity = no of moles ÷ volume
According to this question, 5.0 grams of KCl is dissolved in 500 ml of water. The concentration is calculated as follows:
no of moles of KCl = 5g ÷ 74.5g/mol = 0.067mol
Molarity = 0.067mol ÷ 0.5L = 0.134M
Therefore, if 5.0 grams of KCl is dissolved in 500 ml of water, the concentration of the resulting solution will be 0.134M.
Learn more about concentration at: brainly.com/question/10725862
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