Well ask yourself why don't we count it in moles and you should get your answer.
Answer:
They are the same types of atoms.
Explanation:
Answer:
221.37 u
Explanation:
The formula for the calculation of the average atomic mass is:
Given that:
For first isotope:
% = 65.51 %
Mass = 223.95 u
For second isotope:
Since the element has only 2 isotopes, so the percentage of second is 100 - first percentage.
% = 100 % - 65.51 % = 34.49 %
Let, Mass = x u
Given, Average Mass = 223.06 u
Thus,
Solving for x, we get that:
x = 221.37 u
<u>Thus mass of second isotope = 221.37 u</u>
Answer:
58.44 g of NaCl are needed.
Explanation:
Given data:
Mass of NaCl needed = ?
Volume of solution = 200 mL (200/1000 =0.2 L)
Molarity of solution = 5 M
Solution:
We will solve this problem through molarity formula.
Molarity is used to describe the concentration of solution. It tells how many moles are dissolve in per litter of solution.
Formula:
Molarity = number of moles of solute / L of solution
Now we will put the values.
5 M = moles of solute / 0.2 L
Moles of solute = 5 mol/L × 0.2 L
Moles of solute = 1 mol
Mass of sodium chloride:
Mass = number of moles × molar mass
Mass = 1 mol × 58.44 g/mol
Mass = 58.44 g
Thus, 58.44 g of NaCl needed.
Answer:
The two observations we made from viewing the solar system model are as follows as:
1). When we look at the sky we observe that the motions of all the planets and the stars are perfect circular movements with a good and high speed, but not in velocity because in velocity direction doesn't charges.
2). The sun is at the centre of our solar system and all the planets are equidistant to each other planets and also revolve around the sun.