Li2O + H2O → 2LiOH
This is the answer
3rd blank write 2
<u>Answer:</u> The fraction of atom's mass contributed by nucleus is 0.99
<u>Explanation:</u>
Nucleons are defined as the sub-atomic particles which are present in the nucleus of an atom. Nucleons are protons and neutrons.
The isotopic symbol of Helium-4 atom is 
Number of electrons = 2
Number of protons = 2
Number of neutrons = 4 - 2 = 2
We are given:
Mass of He-4 atom = 
Mass of 1 electron = 
Calculating the mass contributed by the nucleus = 
Mass of the nucleus of He-4 atom = 
To calculate the fraction of atom's mass contributed by the nucleus, we use the equation:

Putting values in above equation, we get:

Hence, the fraction of atom's mass contributed by nucleus is 0.99
Answer: The mass is 980.6g of Gold.
Explanation:
We begin by looking for the number of moles equivalent to 3.0 x 10^24 gold atoms.
Using the Avogadro's number,
6.02 x 10^23 atoms of gold make up 1 mole of gold.
3.0 x 10^24 atoms would make up: 1 / 6.02 x 10^23 x 3.0 x 10^24 = 4.98moles.
Now that we know the number of moles, we can then look for the mass using the formular:
Moles = mass/ molar mass
4.98 = mass / 196.9 (atomic mass of gold)
Making "mass" the subject of formula : mass = 4.98 x 196.9= 980.6g
First, we need to know what's the gravity value in the moon. it is 1.622 m/ s2
to find the force, let's recall this formula----> Force= mass x gravity
force= 83 kg x 1.622= 134.6
A is the closest choice.
(i) We start by calculating the mass of sugar in the solution:
mass of sugar = concentration × solution mass
mass of sugar = 2.5/100 × 500 = 12.5 g
Then now we can calculate the amount of water:
solution mass = mass of sugar + mass of water
mass of water = solution mass - mass of sugar
mass of water = 500 - 12.5 = 487.5 g
(ii) We use the following reasoning:
If 500 g solution contains 12.5 g sugar
Then X g solution contains 75 g sugar
X=(500×75)/12.5 = 3000 g solution
Now to get the amount of solution in liters we use density (we assume that is equal to 1):
Density = mass / volume
Volume = mass / density
Volume = 3000 / 1 = 3000 liters of sugar solution