Atoms are the basic units of matter and the defining structure of elements. We count the number of atoms by the total number of elements present in the compound. In this case, we have 1 atom of Si and 2 atoms of oxygen which would have 3 total number of atoms.
Answer:
Refer to your periodic table. Lewis dot structures are based off the number of valence electrons an atom has.
Looking at the compounds, we can see that Gallium has three valence electrons in its outer shell and oxygen has six. Oxygen and Gallium are going to share electrons with one another, making a V shape in their diagram.
One Oxygen would make a double bond with a Gallium, leaving one valence electron to another oxygen. That oxygen takes that Final electron. It now has 7 in its outer shell. The remaining Gallium and Oxygen do the same double bond as the one before, leaving the 7 valence electron oxygen with one more electron.
Answer: obey the "law of conservation of mass".
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Answer:
grams of sodium phosphate must be added to 1.4 L of this solution to completely eliminate the hard water ions
Explanation:
We will first write the balanced equation for this scenario
3 CaCl2 + 2 Na3PO4 ----> 6 NaCl + Ca3 (PO4)2
3 Mg(NO3)2 + 2 Na3PO4 -----> 6 NaNO3 + Mg3 (PO4)2
The ratio here for both calcium chloride and magnesium nitrate is 
The number of moles of each compound is equal to
Using the mole ratio of 3:2, convert each to moles of sodium phosphate.
mole of CaCl2 is equal to 
Na3PO4
mole of CaCl2 is equal to 
Na3PO4
Converting moles of sodium phosphate to grams of sodium phosphate we get
g/mol
grams of sodium phosphate must be added to 1.4 L of this solution to completely eliminate the hard water ions
