Water is a pure substance because it is not refined like the other materials. Hope this helps!!!
Answer: Sharp spines and waxy stems
Answer:
-2
Explanation:
Calcium is the element of second group and forth period. The electronic configuration of Calcium is - 2, 8, 8, 2 or 
There are 2 valence electrons of Calcium.
Thus, calcium loses two electrons to sulfate ion and sulfate ion accepts these electrons to form ionic bond.
Calcium sulfate, 
is formed when 2 valence electrons of calcium are loosed and they are gained by sulfate ion.
Thus, the charge on the sulfate ion is -2.
Answer:
1,300,000,000,000
Explanation:
1.3 x 10^12
We want to convert this from scientific notation.
Tip: in scientific notation the exponent tells you how many place you move the decimal point over. If the exponent is negative you move the decimal point to the left. Ex. For, 4.1 x 10^-8, we would move the decimal point over 8 times to the left to get .00000041. When the exponent is positive we move over to the right. Ex. For, 7.6 x 10^7 we would move the decimal point over 7 times to the right to get 76,000,000
So to convert 1.3 x 10^12 we simply move over the decimal point over 12 times to the right.
1.3 x 10^12 ------> 1,300,000,000,000
Our answer is 1,300,000,000,000
