Answe
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Explanation:
We use the equation:
Mass = Number of moles * Molecular or atomic mass
Since the number of moles is 1 ("one mole of carbon-12 atoms") and the atomic mass of carbon-12 atoms is 12, hence the mass would be 12 grams. Note that the unit grams (g) is used here, as it is the SI unit for mass measurement.
Number of particles in 1 mole = 6.023 × 1023
Mass of 1 electron = 9.10938 × 10-28 gm
Mass of 1 mole of electrons = 6.023 × 1023 × 9.10938 × 10-28 = 5.486 × 10 -4
Mass of 1 proton = 1.67262 × 10 -24 gm
Mass of 1 mole of protons = 6.023 × 1023 × 1.67262 × 10 -24 gm = 1.007 gm
Mass of 1 neutron = 1.67493 × 10-24 gm
Mass of 1 mole of neutron = 1.67493 × 10-24 × 6.023 × 1023 = 1.008 gm
The % yield if 200g of chlorine react with excess Potassium bromide to produce 410g of bromine is calculated as below
% yield = actual yield/theoretical yield x100
the actual yield = 410 grams
calculate the theoretical yield
by first calculate the moles of chlorine used
mole= mass/molar mass
molar mass of Cl2 = 35.5 x2= 71 g/mol
moles= 200g/71g/mol = 2.82 moles
cl2 +2 KBr = 2KCl +Br2
by use of mole ratio between Cl2 to Br2 which is 1:1 the moles of Br2 is also = 2.82 moles
theoretical mass = moles x molar mass
molar mass of Br2= 79.9 x2= 159.8 g/mol
moles= 2.82g x 159.8 g/mol = 450.64 grams
% yield is therefore = 410g/450.64 x100 = 90.98 %
Answer:
Binomial Naming System
Explanation:
He was the first to use the system, he used it frequently enough for the system to be accepted and used more often by scientists. He believed that species were unable to be changed.
"S<span>cientists believe that solids are mostly open space" is the statement among the statements given in the question that is true. The correct option among all the options that are given in the question is the second option or option "B". I hope that this answer has actually come to your help.</span>
<span>Sulfur Hexachloride
SCl6 So now we count the number of valence electrons each has by seeing what column it's in, (1-8) not counting the columns of the transition metals.
Since Sulfur is in the 6th and Chlorine is in the 7th, and there are 6 chlorines, we can add up all their valence electrons:
6*1+7*6=48 valence electrons.
But remember that electrons come in pairs, either in bonds or as lone pairs. So I usually divide the valence electron number by 2 and just think about placing pairs. It's up to you, but I think it's convenient since we can count "1" in our mind each time we place a bond or a electron pair. So we need to place 24 pairs/bonds.
So we can guess that sulfur is a central atom and draw out a bond from sulfur to each chlorine. Since Sulfur is in the 3rd row it can use d-orbitals to break the octet rule. So when we bond all the chlorines onto sulfur we get:
(see the figure)
and
</span><span>So we made 6 bonds, that means we used up 12 electrons, so if you're counting (AND YOU SHOULD BE!) you have 36 electrons or simply 18 electron pairs left to place. Now let's give chlorine a neutral charge.</span>