Mass percentage is another way of expressing concentration of a substance in a mixture. Mass percentage is calculated as the mass of a component divided by the total mass of the mixture, multiplied by 100%. It is calculated as follows:
% CaCO3 = (<span>1.82g of calcium carbonate</span> / (1.05 g SiO2 + 0.69 g of cellulose + <span>1.82g of calcium carbonate)) x 100% = 51.12% Calcium carbonate</span>
Answer:
b) 0.47
Explanation:
MwC5H12 = 72.15g/mol
⇒mol C5H12 = (10.0)*(mol/72.15)=0.1386molC5H12
MwC6H14=86.18g/mol
⇒molC6H14=(20.0)*(mol/86.18)=0,232
MwC6H6=78.11g/mol
⇒molC6H6=(10.0)*(mol/78.11)=0.128molC6H6
<h3>XC6H14=(0.232)/(0.1386+0.232+0,128)=0.465≅0.47</h3>
Answer:
Because milk has higher KE than ice, KE is transferred from the milk to the molecules of ice.
Explanation:
The best statement that expresses the transfer of kinetic energy(K.E) is that kinetic energy is transferred from the milk to the ice.
Kinetic energy is form of energy due to motion of the particles of a medium. In this regard, we are dealing with heat energy.
- Heat energy is dissipated from a body at higher temperature to one at a lower temperature.
- Ice is at a lower temperature which is 0°C
- Heat will be transferred in form of thermal energy from the body at higher temperature to one with a lower temperature.
- This is from the milk to the molecules of ice.
Answer:
The atomic mass of second isotope is 7.016
Explanation:
Given data:
Average Atomic mass of lithium = 6.941 amu
Atomic mass of first isotope = 6.015 amu
Relative abundance of first isotope = 7.49%
Abundance of second isotope = ?
Atomic mass of other isotope = ?
Solution:
Total abundance = 100%
100 - 7.49 = 92.51%
percentage abundance of second isotope = 92.51%
Now we will calculate the mass if second isotope.
Average atomic mass of lithium = (abundance of 1st isotope × its atomic mass) +(abundance of 2nd isotope × its atomic mass) / 100
6.941 = (6.015×7.49)+(x×92.51) /100
6.941 = 45.05235 + (x92.51) / 100
6.941×100 = 45.05235 + (x92.51)
694.1 - 45.05235 = (x92.51)
649.04765 = x
92.51
x = 485.583 /92.51
x = 7.016
The atomic mass of second isotope is 7.016
ANSWER: B. 20 grams since no matter was added or removed
Hope it helps!
