<span>#1 is air radon, #2 is x-ray, #3 is ground, #4 is cosmic radiation, #5 is TV tube, #6 is weapons test fallout . That's all I got hope I helped!</span>
Answer:
a. because it is an element
Explanation:
its pure because it only has one type of atom, making it an element
Method:
1) Find the atomic number in a periodic table: the number of electrons equal the atomic number
2) Use Aufbau rule
Element atomic number electron configuration
<span>
P 15 1s2 2s2 2p6 3s2 3p3
Ca 20 </span><span><span>1s2 2s2 2p6 3s2 3p6 4s2
</span>Si 14</span><span> 1s2 2s2 2p6 3s2 3p2
S 16</span><span><span> 1s2 2s2 2p6 3s2 3p4
</span>Ga 31. </span><span><span> 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p</span> </span>
Answer:
-0.276 Degrees C
Explanation:
kf of water is 1.86
Freezing point depression= m x kf x i
i= ions present ( K+ Cl-) 1=2
1.86x2X.743= .276
Since its freezinf point depression the freezing point will lower
so
0-.276= -.276
Among the choices, bromine exists as liquid under standard temperature and pressure conditions. Unlike other diatomic molecules which exist as gases, due to its heavy molecular weight, it exists as solid. Francium and cesium are solids while iodine is gas.Answer is 1.
