Answer:
4Cr + 3O2 —> 2Cr2O3
Explanation:
Information from the question include:
Chromium + oxygen -> chromium(III) oxide
From the word equation given above, the equation can be written as follow:
Cr + O2 —> Cr2O3
The equation can be balance by doing the following:
There are 2 atoms of O on the left side and 3 atoms on the right side. It can be balance by putting 2 in front of Cr2O3 and 3 in front of O2 as shown below:
Cr + 3O2 —> 2Cr2O3
Now, we have 4 atoms of Cr on the right side and 1 atom on the left. It can be balance by putting 4 in front of Cr as shown below:
4Cr + 3O2 —> 2Cr2O3
Now the equation is balanced
Answer:
a)22.2°C after adding magnesium
b)17.3°C before adding magnesium
c) 4.9 is change
Answer: 11.5 grams
Explanation:
Molarity of a solution is defined as the number of moles of solute dissolved per Liter of the solution
where,
Morality = 0.612 M
n= moles of solute
= volume of solution in ml = 100 ml
Now put all the given values in the formula of molarity, we get

Therefore, the mass of copper (II)nitrate required is 11.5 grams
Change the places of 'acts against the motion of an object' and 'causes an object to change speed or direction'
Answer:
• Molecular mass of Iron (III) tetraoxide

[ molar masses: Fe → 56, O → 16 ]
