1)
a)
D = 0.79 g/cm³ m = 85.1 g
D = m / V
0.79 = 85.1 / V
V = 85.1 / 0.79 => 107.72 cm³
____________________________________________
b) D = m / V
0.79 = m / 125
m = 0.79 x 125 => 98.75 g
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hope this helps!
2.2 x 10^-2
0.055 / 250 = 0.00022 - This would be 2.2 x 10^-4, but the question is asking for percent, not proportion, so multiply by 100% to get the percentage.
0.00022 * 100% = 0.022% = 2.2 * 10^-2
Answer:
The mass of
4.6
×
10
24
atoms of silver is approximately 820 g.
Explanation:
In order to determine the mass of a given number of atoms of an element, identify the equalities between moles of the element and atoms of the element, and between moles of the element and its molar mass.
1
mole atoms Ag=6.022xx10
23
atoms Ag
Molar mass of Ag =#"107.87 g/mol"#
Multiply the given atoms of silver by
1
mol Ag
6.022
×
23
atoms Ag
. Then multiply times the molar mass of silver.
4.6
×
10
24
atoms Ag
×
1
mol Ag
6.022
×
10
23
atoms Ag
×
107.87
g Ag
1
mol Ag
=
820 g Ag
Answer:
Option C. 4.03 g
Explanation:
Firstly we analyse data.
12 % by mass, is a sort of concentration. It indicates that in 100 g of SOLUTION, we have 12 g of SOLUTE.
Density is the data that indicates grams of solution in volume of solution.
We need to determine, the volume of solution for the concentration
Density = mass / volume
1.05 g/mL = 100 g / volume
Volume = 100 g / 1.05 g/mL → 95.24 mL
Therefore our 12 g of solute are contained in 95.24 mL
Let's finish this by a rule of three.
95.24 mL contain 12 g of sucrose
Our sample of 32 mL may contain ( 32 . 12) / 95.24 = 4.03 g
Answer:
In strict SI units (highly recommended), express n in moles, R is the universal gas constant R=8.314Jmol−K , T is the temperature in Kelvins, and the volume V is in m3 . The resulting pressure P will be in Pa. R=0.082054L−atmmol−K , in which case the pressure is calculated in atm.
