Given a mole each for iron and magnesium, the number of atoms of each element is equal. Iron has a greater mass due to its greater molecular weight. The correct statement among the choices is D.
2HCO3 - + Ca2+ CaCO3 + CO2 + H2O Bicarbonate (HCO3-) combines with calcium ions in the water to make calcium carbonate (CaCO3, limestone). This process can occur both within organisms such as corals or as a simple chemical reaction in the water itself.
This is a tricky question. All that matters are ratios of percentages, not percentages themselves. So no one should directly compare 27.2 with 42.9. We must and shall compare the ratios (27.2 to 72.8) and (42.9 to 57.1).
Take them both down to 1 to and see what happens.
Working out the formulas knowing atomic masses is a bit beside the point; this is how people first DISCOVERED the idea of atomic mass.
A
Carbon Oxygen
27.2g 72.8g (100-27.2)
Moles 27.2/12 72.8/16
2.27 4.55
Ratio 1 2
Do the same with the other
Periodic Trend:
The Atomic radius of atoms generally decreases from left to right across a period
Group Trend:
The atomic radius of atoms generally increases from top to bottom within a group. As atomic number increases down a group, there is a increase in the positive nuclear charge, however the co-occurring increase in the number of orbitals wins out, increasing the atomic radius down a group in the periodic table
Answer :
The Atom with the greatest atomic radius is chlorine. Fluorine can be ruled out because it is in the same period as oxygen and further to the right down the period. Chlorine has the largest atomic size because it is farthest down the group of any of the above elements listed.
