What is the difference between a quantity and a unit?
Answer:
Physical quantities are a characteristic or property of an object that can be measured or calculated from other measurements. Units are standards for expressing and comparing the measurement of physical quantities. All units can be expressed as combinations of four fundamental units.
Hope this helps!!!
<span>The answer should be false, because mass should not have to do with how bright a star is
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Answer:
[NaCl]: 2M
Explanation:
This solution is made of NaCl therefore:
Our solute is NaCl
Moles of solute: 4
Our solution's volume is 2L
Molarity are the moles of solute contained in 1L of solution (mol/L)
[NaCl]: 4 mol /2L = 2M
We can also make a rule of three:
In 2 L we have 4 moles of solute
So, In 1 L we must have (1 . 4) /2 = 2 M
Answer:
For the production of 77.4 L water 90.3 L oxygen is required.
Explanation:
Given data:
Volume of oxygen required = ?
Volume of water produced = 77.4 L
Solution:
Chemical reaction equation:
2C₂H₆ + 7O₂ → 4CO₂ + 6H₂O
1 mole = 22.414 L
There are 6 moles of water = 6×22.414 = 134.5 L
There are 7 moles of oxygen = 7×22.414 = 156.9 L
Now we will compare the litters of water and oxygen:
H₂O : O₂
134.5 : 156.9
77.4 : 156.9/134.5×77.4 =90.3 L
So for the production of 77.4 L water 90.3 L oxygen is required.
