Answer:
B
Explanation:
The carbon-oxygen double bond is polar.
However, carbon dioxide is a linear molecule. The two dipoles cancel out each other.
Thus, carbon dioxide is a non polar molecule with polar bond.
a) The reaction is exothermic since the overall enthalpy change is negative. this means that the system has lost energy to the environment, namely, the apparatus and due to drought.
b) We first calculate the number of moles in 3.55 grams of magnesium.
number of moles= mass/ atomic mass
=3.55/24
=0.1479 moles(to 4sf)
now, if 2 moles of magnesium give -1204kJ
How much energy is given by 0.1479 moles
= (0.1479×-1204kJ)
=-89.0358kJ (don't forget the negative sign)
c) two molesof MgO produces -1204kJ of energy
then -234kJ will be produced by
=(-234kJ×2moles)/1204kJ
=0.3887moles
one mole of MgO weighs 24+16=40
therefore the mass produced is 0.3887moles×40=15.548grams
(d) we first find the number of moles of MgO in 40.3 grams
number of moles=mass/RFM
=40.3g/40= 1.0075moles
if 2 moles of MgO give 1204 kJ then decomposing 1.0075 moles requires
(1.0075 moles×1204kJ)/2=606.515kJ
Answer:
Ionic bond
Explanation:
Covalent bonds can only form between non-metals and copper is a metal so it would be an ionic bond.
Answer:
2/3 cup of semisweet chocolate
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.