Given :
Number of molecules of 
.
To Find :
How many moles are in given number of molecules.
Solution :
We know, in 1 moles of any element/compound contains 
at atoms/molecules.
So, number of moles in 
molecules are :
Therefore, number of moles are 8.97 .
Answer:
C. 17 grams.
Explanation:
∵ mass % = [mass of solute/mass of solution] x 100.
mass of solute (NaCl) = ??? g & mass of solution = 140.0 g.
<em>∴ mass of NaCl = (mass %)(mass of solution)/100 </em>= (12.0)(140.0)/100 = <em>16.80 g ≅ 17.0 g.</em>
Answer:
B and BBr3
Explanation:
1) 3HBr + B = BBr3 + H2 (double all equation because H2)
2) 6HBr + <em>2B </em>= <em>2BBr3</em> + 3H2
Explanation:
When a brick is heated to a temperature between 20°C and 150°C, it loses most of the water added to the clay during the preparation phase. ... When the temperature starts to rise over 600°C, chemical changes begin to occur in the clay which give the brick colour, hardness and durability.
Answer:
it needs two electrons in the first and eight to fill the second.
Explanation:
Because neon has two atomic shells, it needs two electrons in the first and eight to fill the second. Neon has a total of ten electrons which means two filled shells.
