Answer: The second choice
Explanation: The question is most likely asking what the arrow's pointing at, and it's right at the meeting point for lines x and y. Lines x and y would be the common ancestors of the point the arrow is showing since they're above the point and meet up to the point.
A True
Each element consists of one type of atom but, not contains only one atom. It has same type of atoms present in it.
When acids react with water, H ions are released which then combine with water molecules to form H₃O⁺
The conversions that will be used are:
1 mole of copper / 63.5 grams of copper
6.02 x 10²³ atoms of copper / 1 mole of copper
Multiplying the given mass by these conversions,
660 g * (1 mol Cu / 63.5 g Cu) * (6.02 x 10²³ Cu atoms / 1 mole Cu)
The sample contains 6.25 x 10²⁴ atoms of copper
there are valence electrons 3 in group 10.