Elements can combine to form molecules, like o2 or co2. elements combine to form molecules and these elements are joined together by chemical bonds i.e covalent bond in this molecule so option A is correct
hope this helps
As we know that there are avogadro no. of atoms in 9 g of beryllium.
1 mole of beryllium = 6.02 * 10^23 atoms
so 2.5 mole= 6.02*10^23*2.5 i.e = <span>15.055 × 10^23 atoms </span>
1.7 km^2 already has two significant figures.
Answer:
I kinda forgot. I'm sorry if I didn't answer your question.
Explanation:
Answer:
See explanation
Explanation:
Molar mass of NaCl = 58.5 g
Number of moles contained in 10 g of NaCl = 10 g/58.5 g = 0.17 moles
If 1 mole of NaCl contains 6.02 * 10^23 atoms
0.17 moles of NaCl contains 0.17 * 6.02 * 10^23 atoms = 1.02 * 10^23 atoms
Molar mass of Fe II chloride = 126.751 g/mol
Number of moles = 10 g/126.751 g/mol = 0.0789 moles
Number of atoms = 0.0789 moles * 6.02 * 10^23 atoms = 4.7 * 10^22 atoms
Molar mass of Na = 23 g/mol
Number of moles = 10g/23 g/mol = 0.43 moles
Number of atoms = 0.43 moles * 6.02 * 10^23 atoms = 2.59 * 10^ 23 atoms
