B) loses electrons and is oxidised
Its oxidation number is 0 in Co(s) and +2 in Co(C2H302)2(aq), hence it gets oxidised
The mass of carbon dioxide produced from the complete combustion of 4.80 x10^-3 g of methane is 0.0132 grams
calculation
write the equation for combustion of methane (CH4)
CH4 + 2O2 → CO2 + 2H2O
find the moles of CH4 used = mass/molar mass
molar mass of CH4 = 12 +(1 x4) = 16 g/mol
moles =( 4.80 x10^-3 g) / 16 g/mol = 3 × 10^-4 moles
by use of mole ratio between Ch4 to CO2 which is 1:1 the moles of CO2 is also = 3 x10^-4 moles
mass of CO2 is therefore = moles x molar mass of Co2
The molar mass of Co2 = 12 +(16 ×2) = 44 g/mol
mass is therefore = (3 ×10^-4 moles) ×44 g/mol = 0.0132 grams
Galvanizing protects from rust in a number of ways: It forms a barrier that prevents corrosive substances from reaching the underlying steel or iron. The zinc serves as a sacrificial anode so that even if the coating is scratched, the exposed steel will still be protected by the remaining zinc.
Answer:
Percent Composition of Compounds
The percent composition (by mass) of a compound can be calculated by dividing the mass of each element by the total mass of the compound.
LEARNING OBJECTIVES
Translate between a molecular formula of a compound and its percent composition by mass
- The atomic composition of chemical compounds can be described in a variety of ways, including molecular formulas and percent composition.
- The percent composition of a compound is calculated with the molecular formula: divide the mass of each element found in one mole of the compound by the total molar mass of the compound.
- The percent composition of a compound can be measured experimentally, and these values can be used to determine the empirical formula of a compound.
- percent by mass: The fraction, by weight, of one element of a compound.
- The atomic composition of chemical compounds can be described using a variety of notations including molecular, empirical, and structural formulas. Another convenient way to describe atomic composition is to examine the percent composition of a compound by mass.
- Percent Composition by Mass
Percent composition is calculated from a molecular formula by dividing the mass of a single element in one mole of a compound by the mass of one mole of the entire compound. This value is presented as a percentage.
Explanation:
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