Answer : The mass of the water molecule is 4.5 times greater than the mass of the helium atom.
Explanation :
Assumption : The number of water molecules is equal to the number of helium atoms
Given : The mass of water = 4.5 × The mass of helium ........(1)
The mass of Water = Mass of 1 water molecule × Number of water molecule
The mass of Helium = Mass of 1 helium atom × Number of helium atom
Now these two masses expression put in the equation (1), we get
Mass of 1 water molecule × Number of water molecule = 4.5 × Mass of 1 helium atom × Number of helium atom
As per assumption, the number of water molecules is equal to the number of helium atoms. The relation between the mass of water molecule and the mass of helium atom is,
Mass of water molecule = 4.5 × Mass of helium atom
Therefore, the mass of the water molecule is 4.5 times greater than the mass of the helium atom.
<span>85% ethanol | 25% ethanol | 50% ethanol
x | y | 20 gal
use x and y because you don;t know how much she needs.
0.85x | 0.25y | 20(0.5)
85% is 85/100 or 0.85, and you need that much of x, same goes for the 25% and 50% mixtures so now you can make up 2 equations
1) x + y = 20 2) 0.85x + 0.25y= 10 (you get 10 when you multiply 20 by 0.5) now you can solve for x or y using substitution.
first rewrite 1) in terms of x or y: x+ y= 20 ----> y= 20 - x now you can substitute 20- x for y in the second equation.. 0.85x + 0.25y= 10 0.85x + 0.25(20-x)= 10 distribute here..(0.25 * 20 and 0.25 * (-x) ) 0.85x + 5 - 0.25x = 10 combine like terms 0.6x +5 = 10 move the 5 over to the other side 0.6x= 10 -5 0.6x = 5 divide both sides by 0.6 x= 25/3 or 8.3 now you know the amount of x so you can substitue this back into the first equation to find y. 0.85x + 0.25y= 10 0.85(25/3) +0.25y= 10 85/12 + 0.25y= 10 0.25y = 10- 85/12 0.25y= 35/12 y= 35/3 or 11.6 you can check by putting these values into the euations: 1) x+ y= 20 25/3 + 35/3 =20 20= 20 good so far 2) 0.85x + 0.25y= 10 0.85(25/3) + 0.25(35/3)=10 10 = 10
so our values for x and y work
x= 25/3 and y= 35/3</span>
Answer:
European Union was on grand committee
Answer:
We typically represent covalent bonds with a dash ( - ) between the atoms. This indicates a single bond. Ex: Cl - Cl
Single bond, double bond, triple bond.
Explanation:
We call it a single covalent bond because the atoms are sharing a single pair of electrons.