Answer:
1. Density can be used to identify a substance
2. Density can be used to ascertain whether a substance will float in water.
Explanation:
The calculation of the density of a substance can be used to identify the substance. If the density of a substance is calculated accurately, and compared with a table of standard densities, then we can identify that substance.
Also, density determines whether an object will float or sink in water. If an object is less dense than water then it will float in water. If it is denser than water, then it will sink in water.
Answer:
Option a: positron emission.
Explanation:
In the transformation we have:
⁶⁷Ga → ⁶⁷Zn
The reaction is:
For Ga to become Zn, the atom nucleus has to lose a proton, so in the given options, the reaction that involves the transformation of a proton is the option a, positron emission.
In a positron emission, a proton becomes into a neutron and a positron:
Therefore, the correct answer is option a: positron emission.
I hope it helps you!
<span>4FeS2 + 11O2 = 2Fe2O3 + 8SO2</span>
Percent yield is calculated as the actual yield divided by the theoretical yield multiplied by 100.
Actual yield = 55 g ( 1 mol / 159.69 g ) = 0.34 mol Fe2O3
To find for the theoretical yield, we first determine the limiting reactant.
100 g O2 ( 1 mol / 32 g) = 3.13 mol O2
200 g FeS2 (1 mol / 119.98g) = 1.67 mol FeS2
Therefore, the limiting reactant is O2.
Theoretical yield = 3.13 mol O2 ( 2 mol Fe2O3 / 11 mol O2 ) = 0.57 mol Fe2O3
Percent yield = (0.34 mol / 0.57 mol) x 100 = 59.74%
So they can tell what exact species it is.
The answer is atoms good luck
