Answer: A new model of the atom that described electrons as being in a cloud
Explanation:
Answer:
B. 0.2.
Explanation:
<em>n = mass/molar mass</em>
mass of CaCO₃ = 20 g, molar mass of CaCO₃ = 100.0869 g/mol.
<em>∴ n = mass/molar mass = </em>(20 g)/(100.0869 g/mol) <em>= 0.1998 ≅ 0.2 mol.</em>
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<em>So, the right choice is: B. 0.2.</em>
Answer:
Explanation:
1 mol of sodium = 23 grams (use the number on your periodic table).
0.7350 mol sodium = x
Cross multiply
1*x = 0.7350 * 23
x = 16.905
You will get slightly less than this, depending on your periodic table. But the method will be the same.
Carbon has 4 valence electrons so to gain a noble gas electron configuration, which has 8 valence electrons and is the most electrically stable, carbon needs 4 more electrons.
The metalloids are on the right side of the periodic table B, Si, Ge, As, Sb, Te, and At. The nonmetals are also on the right side next to the metalloids, there should be a He at the top right of the periodic table and there should be one more nonmetal at the top left of the periodic table that is H. And from the metals they are all on the middle next to the metalloids, starting from Li, Be, Na, and Mg as so on all of those are metals.