The sand provides a rough surface on top of the ice for the cars' tires to grip onto. It provides more friction. Salt melts the ice and often provides more friction (the disadvantage is that it eats concrete!).
B. The atomic number ........
Answer:
it is because they are placed geographically different.
Answer:
given an element U of relative atomic mass 10.8 for example with isotopes U-10 and U-11 we can get their percentages by the following steps.
Explanation:
1:let the Percentage of U-10 equal to X% and percentage of U-11equal to Y%.
2:The addition of X% and Y% equal to 100%.
3:X%=100%-Y%
4:X% of U-10 +Y% of U-11=10.8
5: substitute 3 in 4.
6: i.e (100-Y)% of U-10+Y% of U-11=10.8.
7:(100-Y)/100 of 10 +Y/100 of 11=10.8.
8:100-Y/10 +11Y=10.8.
9:(1000-10Y+11Y)/100=10.8.
10:1000+Y=10.8*100
11:1000+Y=1080.
12:Y=1080-1000.
13:Y=80.
14: from 3,X=100%-Y%.
X=100%-80%=20%.
15: Therefore, the percentage of isotopes in the isotopic mixture are 20% U-10 and 80% U-11.
Answer:
B
Explanation:
Valence electrons only involve in chemical bonding, since they are farthest from the nucleus. Hope this helps!