6.022x10^23 is Avogadro’s number. Use this whenever you work with Stoichiometry involving Atoms, formula units, or molecules. 1 mol of anything is always Avogadro’s number.
Multiply everything on the top= 6.93 x 10^23
Divide by everything on the bottom = 6.93 x 10^23
Answer: 6.93 x 10^23 atoms Cu.
The formula for density is:
D = m/v
We can use the formula to figure out the mass because we already know two of the three values (we are given the density and volume), so we only have to solve for <em>m. </em>If we plug our given values into the formula, we get:
2.70 = m / 264
Now, all we need to do is solve for <em>m</em>. The goal is to get <em>m</em> on one side of the equation, and all we have to do is multiply each side of the equation by 264:
264 × 2.70 = (m÷264) × 264
264 × 2.70 = m
m = 712.8
The mass of the piece of aluminum is 712.8 grams.
Answer:
They all have the same number of atoms
Explanation:
Which of the following has more atoms?
One mole of zinc
One mole of gold
One mole of silver
One mole of magnesium contians
O They all have the same number of atomst
a mole of anything contains Avogadros number of 6.022X10^23 things
which has the greatest number of thing? a dozen eggs, a dozen cookies, a dozen pizzas?
a dozen is a number means 12
a mole is a number that that means 6.022 X 10^23 you calculate the molar mass from the chemical formula, but every j mole contains 6.022X10^23
particles.
just like every dozen contains 12
so
They all have the same number of atoms
Where’s the chart and scientists?
The correct option is A.
To calculate the binding energy, you have to find the mass defect first.
Mass defect = [mass of proton and neutron] - Mass of the nucleus
The molar mass of thorium that we are given in the question is 234, the atomic number of thorium is 90, that means the number of neutrons in thorium is
234 - 90 = 144.
The of proton in thourium is 90, same as the atomic number.
Mass defect = {[90 * 1.00728] +[144* 1.00867]} - 234
Note that each proton has a mass of 1.00728 amu and each neutron has the mass of 1.00867 amu.
Mass defect = [90.6552 + 145.24848] - 234 = 1.90368 amu.
Note that the unit of the mass is in amu, it has to be converted to kg
To calculate the mass in kg
Mass [kg] = 1.90368 * [1kg/6.02214 * 10^-26 = 3.161135 * 10^-27
To calculate the binding energy
E = MC^2
C = Speed of light constant = 2.9979245 *10^8 m/s2
E = [3.161135 * 10^-27] * [2.9979245 *10^8]^2
E = 2.84108682069 * 10^-10.
Note that we arrive at this answer because of the number of significant figures that we used.
So, from the option given, Option A is the nearest to the calculated value and is our answer for this problem.