Answer:
Mass: 981.0 g
Density: 5.61 g/cm^3
Hardness: = 2.5 - 3
Unknown material: Chalcocite
Explanation:
1 kg = 1000g
2.43 kg *1000g/1kg = 2430 g
Chemists use balanced chemical equations as a basis to calculate how much reactant is needed or how much product will be formed in a reaction.
Answer:
<u>B</u> What role do animals have in the carbon cycle?
Group of answer choices
use water and release oxygen
<u>use sugar and release carbon</u>
use carbon and release oxygen
use carbon and release nitrogen
<u>D, E</u> Select TWO statements that describe what the scientists will observe in the ecosystem after fossil fuels have been extracted and burned.
Group of answer choices
There is more available space for carbon to become fossil fuels.
There is less carbon in storage.
There will be less carbon in the water.
<u>There is more carbon in the atmosphere.</u>
<u>There will be more carbon respired by organisms.</u>
There will be less carbon released through decomposition.
Explanation:
Animals obtain energy through sugar from the food they eat and release carbon into the air through respiration. Therefore, they partake in the carbon cycle by using sugar and releasing energy.
As far as the second question, when fossil fuels are burned, the carbon contained within them is released into the atmosphere in the form of carbon dioxide. So, there will obviously be a greater amount in the atmosphere.
I would like to apologise in advance if either of my option choices were incorrect.
Answer:
E. Substance A will be the limiting reactant.
Explanation:
Below is a generic equation for a reaction.
2A + 3B → C + 3DA
According to the balanced equation, the theoretical molar ratio of A to B is 2:3, that is, 2 moles of A react with 3 moles of B.
<em>If I mix 2 units of A, with 6 units of B, which of the following is true?</em>
<em>A. There would be no reaction.</em> FALSE. The reaction will occur until the limiting reactant is over
<em>B. Both reactants will fully react.</em> FALSE.
<em>C. Not enough information given.</em> FALSE.
<em>D. Substance B will be the limiting reactant.</em> FALSE. Substance B will be the reactant in excess because there are 6 moles and only 3 moles are required.
<em>E. Substance A will be the limiting reactant.</em> TRUE.
