The atomic number (it's order in the periodic table) is the same as the number of protons. Since there are 11 protons, it is the 11th element. Referencing the periodic table, that is Sodium, represented by Na.
This is because the statement above fits the definition of a positive economic statement. A Positive economic statement refers to objective statements that can be verified, tested , amended or discarded by consulting available evidence .The statement above can be tested objectively to establish its veracity.
1 mole of methane reacts with 2 moles of oxygen to give 1 mole of CO2 and 2 moles of water so 0.5 mole of methane will be required which is equal to 0.5×16=8g.