It is a physical change when cream mixes with
coffee, it changes the color of the coffee. When you add more or less cream there
is a color change depending on the consistency of cream. The
properties are not changes and a no new compound is formed as in chemical
change with a reaction of two compounds, a new compound is formed with
different properties. So it is a physical change.
Answer:
C₆H₈O₆
Explanation:
First off, the<u> percent of oxygen by mass</u> of vitamin C is:
- 100 - (40.9+4.58) = 54.52 %
<em>Assume we have one mol of vitamin C</em>. Then we would have <em>180 grams</em>, of which:
- 180 * 40.9/100 = 73.62 grams are of Carbon
- 180 * 4.58/100 = 8.224 grams are of Hydrogen
- 180 * 54.52/100 = 98.136 grams are of Oxygen
Now we <u>convert each of those masses to moles</u>, using the <em>elements' respective atomic mass</em>:
- C ⇒ 73.62 g ÷ 12 g/mol = 6.135 mol C ≅ 6 mol C
- H ⇒ 8.224 g ÷ 1 g/mol = 8.224 mol H ≅ 8 mol H
- O ⇒ 98.136 g ÷ 16 g/mol = 6.134 mol O ≅ 6 mol O
So the molecular formula for vitamin C is C₆H₈O₆
The given question is incomplete. The complete question is:
The combustion of propane (C3H8) in the presence of excess oxygen yields 
and 
When only 2.5 mol of 
are consumed in order to complete the reaction, ________ mol of are produced.
Answer: Thus when 2.5 mol of are consumed in their reaction, 1.5 mol of are produced
Explanation:
The balanced chemical equation is:
According to stoichiometry :
5 moles of produce = 3 moles of
Thus 2.5 moles of will produce = 
moles of
Thus when 2.5 mol of are consumed in their reaction, 1.5 mol of are produced
