The density would be the same for the whole bar as well as one half of the bar. Density is a identity I believe, by this I mean that it stays the same no matter how little or how much of the same substance you have. Since density = mass / volume, half the bar has half of the weight as well as half of the volume of the whole bar, making the density the same.
For example, a block weighs 10 grams and has a volume of 5 ml. the density would be d = 10/5 or, d = 2g/ml
Half of the block weighs 5 grams and has a volume of 2.5 ml. The density is d = 5/2.5, or, d = 2 g/ml.
See, although there are different amounts of the same substance, their density is the same.
The answer is
option D "CO." Co also known as
Cobalt is the 27th element on the periotic table. It was discovered in <span>1735, it's boiling point is 3200 k.</span>
Atomic mass: 58.9332
Protons: 27
Neutrons: 32
Electrons: 27
Hope this helps!
Losing eltron is the answer
<span>Well it depends on percentage by what, but I'll just assume that it's percentage by mass.
For this, we look at the atomic masses of the elements present in the compound.
Cu has an atomic mass of 63.546 amu
Fe has 55.845 amu
and S has 36.065 amu
Since there are 2 molecules of Sulfur for each one of Cu and Fe, we'll multiply the Sulfur atomic weight by 2 to obtain 72.13 amu
So we have not established the mass of the compound in amus
63.546 + 55.845 + 72.13 = 191.521
That is the atomic mass of Chalcopyrite. and Iron's atomic mass is 55.845
So to get the percentage, or fraction of iron, we take 55.845 / 191.521
Which comes out to 29.15% by mass
Mass of the sample is not needed for this calculation, but since the question mentions it I would go ahead and check if the question isn't also asking for the mass of Iron in the sample as well, in which case you just find the 29.15% of 67.7g</span>
<span>No. Zn can only have oxidation states of 1+ or 2+. For this compound to be able to exist, the Zn would have to have an oxidation state of 2- to counteract the 2+ from the 2 sodium ions. Sodium ions each have a +1 charge, so the 2 sodium ions would carry a +2 charge. In order for the compound to exist, the net charge between the 2 sodium and 1 zinc atoms would need to be 0.</span>
