This element is called Neon and it is part of the group known as Noble gases or group 8 and it is in period 2
There should be 2 since there’s 2 D atoms in the reaction.
Most chemical elements are solid at room temperature. Some elements exist as gases but only two elements, mercury (Hg) and bromine (Br) are liquids at room temperature (approx 25oC). Hope this helped you!
Explanation:
Note: Molar masses of elements can be found online or in the periodic table.
Moles of Magnesium
= 3.60g / (24.3g/mol) = 0.148mol.
Moles of Chlorine
= 10.65g / (35.45g/mol) = 0.300mol.
Mole ratio of Magnesium to Chlorine
= 0.148mol : 0.300mol = 1 : 2.
Hence we have the empirical formula MgCl2.
Moles of Lithium
= 9.1g / (6.94g/mol) = 1.311mol.
Moles of Oxygen
= 10.4g / (16g/mol) = 0.650mol.
Moles ratio of Lithium to Oxygen
= 1.311mol : 0.650mol = 2 : 1.
Hence we have the empirical formula Li2O.