If the atom is neutral , the atomic number identifies the number of electrons in the atom.
A.
Convert 72g of water into moles of water using molecular weights.
So water is H2O so add up those molecular weights (H=1 and O=16)
2(1)+(16) = 18 g/mol
Then convert so 72g / (18 g/mol) = 4 mol
Now you can convert mol of water to mol of oxygen. So 4 mol of water is 4 mol of oxygen. Then use oxygen molecular weight to find grams again.
4 mol oxygen * 16 g/mol = 64g of oxygen
If we were doing hydrogen instead of oxygen there would be 8 mol hydrogen in 4 mol of water (2 H’s in every H2O molecule) and since we have 74 grams and oxygen is 64 grams, Hydrogen should be 8 grams. Math to check below
8 mol hydrogen * 1 g/mol = 8g of hydrogen
It all adds to 72 so we are correct.
Answer:
Hummingbirds have a very high metabolism and must eat all day long just to survive. They consume about half their body weight in bugs and nectar, feeding every 10-15 minutes and visiting 1,000-2,000 flowers throughout the day.
This ion has 12 protons,12 neutrons and 10 electrons because the element lost 2 electrons and turned to a positive ion
