Answer:
54 g
Explanation:
Given data:
Mass of carbon = 18 g
Mass of CO₂ = 72 g
Mass of oxygen needed = ?
Solution:
Chemical reaction:
C + O₂ → CO₂
according to law of conservation mass, mass can neither be created nor destroyed in a chemical equation.
This law was given by French chemist Antoine Lavoisier in 1789. According to this law mass of reactant and mass of product must be equal, because masses are not created or destroyed in a chemical reaction.
In given photosynthesis reaction:
6CO₂ + 6H₂O + energy → C₆H₁₂O₆ + 6O₂
there are six carbon atoms, eighteen oxygen atoms and twelve hydrogen atoms on the both side of equation so this reaction followed the law of conservation of mass.
In a similar way,
C + O₂ → CO₂
18 g + X = 72
X = 72 -18
X = 54 g
Thus, 54 g of O₂ are required.
Answer:
To determine the amount of heat the gold has absorbed to melt, we simply multiply the mass of the block of ice to the heat of fusion of water which is given above. We calculate as follows:
Heat = 20.0 g (35.4 g)
Heat = 1290 J
Explanation:
A chemical reaction is one in which a chemical change occurs.
During a chemical change;
- The process is irreversible
- New kinds of matter produced
- There is a change in mass
Based on these premise;
Baking cake batter is a chemical reaction because you cannot reverse the process
Shredding a paper is not a chemical reaction because no new kind of matter is produced.
Twisting of a metal wire is not a chemical reaction
Yellowing of newspaper in sunlight is a chemical change. The process cannot be reversed
I believe the answer would be 3( conserved)
