It’s 6.022x10^23. This is how many atoms of any element are in one mole of that element. No matter what it is, there are always 6.022x10^23 atoms per mole. So divide 1.81x10^24 by 6.022x10^23 to get approximately 3 moles of sulfur.
<span>Answer:
For this problem, you would need to know the specific heat of water, that is, the amount of energy required to raise the temperature of 1 g of water by 1 degree C. The formula is q = c X m X delta T, where q is the specific heat of water, m is the mass and delta T is the change in temperature. If we look up the specific heat of water, we find it is 4.184 J/(g X degree C). The temperature of the water went up 20 degrees.
4.184 x 713 x 20.0 = 59700 J to 3 significant digits, or 59.7 kJ.
Now, that is the energy to form B2O3 from 1 gram of boron. If we want kJ/mole, we need to do a little more work.
To find the number of moles of Boron contained in 1 gram, we need to know the gram atomic mass of Boron, which is 10.811. Dividing 1 gram of boron by 10.811 gives us .0925 moles of boron. Since it takes 2 moles of boron to make 1 mole B2O3, we would divide the number of moles of boron by two to get the number of moles of B2O3.
.0925/2 = .0462 moles...so you would divide the energy in KJ by the number of moles to get KJ/mole. 59.7/.0462 = 1290 KJ/mole.</span>
Answer:
42.38875878%
Explanation:
i divided 4.27 g from 1.81g using a percentage calculator but im not sure if its correct
Answer : 12 karat
Explanation : When pure gold is considered to be 24 karat then if its 50 mol% silver and 50 mol% silver then using karat scale calculation;
Karat/24 X 100 = 50 mol% (for gold) in alloy
So, Karat = (50 X 24) / 100 = 12 karat.
Hence the alloy will be of 12 karat.