Answer:
sorry I have no idea what the answer is
The relative mass of the sample : 18.94
<h3>Further explanation
</h3>
The elements in nature have several types of isotopes
Isotopes are atoms whose no-atom has the same number of protons while still having a different number of neutrons.
So Isotopes are elements that have the same Atomic Number (Proton)
Atomic mass is the average atomic mass of all its isotopes
Mass atom X = mass isotope 1 . % + mass isotope 2.%
F-19 = 94% of the sample
F-18 = 100%-94%=6% of the sample
The relative mass :

<em>How do air masses flow?</em>
<em>from regions of high pressure to low pressure</em>
.
In general, cold air masses tend to flow toward the equator and warm air masses tend to flow toward the poles.
Answer:
Pb(NO₃)₂ + Na₂CrO₄ —> PbCrO₄ + 2NaNO₃
The coefficients are: 1, 1, 1, 2
Explanation:
Pb(NO₃)₂ + Na₂CrO₄ —> PbCrO₄ + NaNO₃
The above equation can be balance as follow:
Pb(NO₃)₂ + Na₂CrO₄ —> PbCrO₄ + NaNO₃
There are 2 atoms of Na on the left side and 1 atom on the right side. It can be balance by writing 2 before NaNO₃ as shown below:
Pb(NO₃)₂ + Na₂CrO₄ —> PbCrO₄ + 2NaNO₃
Now the equation is balanced.
The coefficients are: 1, 1, 1, 2
Antimony Tribromide is the answer