Answer:
answer A has four valence electrons
Explanation:
The outer shell has 4 electrons, which are considered the valence electrons
Answer:
1. chloroplast
2. they prevent some proteins to function how they normally function
Explanation:
It would be a solid because at -20 °C it has turned to ice
Answer:
A molecule exists when two or more atoms join together by forming chemical bonds. ... When atoms of at least two different elements come together to form chemical bonds, these molecules can be called compounds. Sodium chloride (NaCl) is a classic example of an ionic compound, or compound formed by ionic bonds.
Explanation:
Answer:
The number of atoms in 20 grams of Pa-234 is 5.14 ×10²² atoms
Explanation:
Given that the molar mass of Pa-234 (protactinium) is 234.04331, we have
The number of moles of protactinium in 20 grams of Pa-234, we have
Number of moles = Mass/(Molar mass) = 20/234.04331 = 0.0855 moles
One mole of Pa-234 contains 6.02×10²³ atoms, therefore, we have;
0.0855 moles of Pa-234 contains 0.0855× 6.02×10²³ = 5.14 ×10²² atoms
Therefore, the number of atoms in 20 grams of Pa-234 = 5.14 ×10²² atoms.
