The elements are listed in order of increasing the atomic number. Its the number that is the number of protons in the nucleus of an atom.
Answer:
A. a magnet
Explanation:
Iron fillings could be separated from sand using a magnet
40.0 g ( 1 mole ) --------------- 6.02x10²³ molecules
? ? --------------------------- 2.90x10²² molecules
mass = 2.90x10²² * 40.0 / 6.02x10²³
mass = 1.16x10²⁴ / 6.02x10²³
mass = 1.9269 g
hope this helps!
<span>You can find
the number of moles in equilibrium if you got the chemical reaction correctly. Make
sure that you got the exact chemical formula of the substance that is reacting
and the yielded product. If you got them, balance the chemical reaction. If the
chemical reaction is balanced, the system is in equilibrium. You can find the
number of moles in equilibrium at the coefficients of the chemical substances
you are balancing. For example, N2 + 3H2 -> 2NH3. The number of moles of N2
is 1, H2 is 3 and NH3 is 2.</span>
