B. an inference.
C. a theory.
D. a controlled experiment.
The reaction between ethanol and oxygen must be a combustion reaction to give carbon dioxide and water as products.
The reaction between ethanol, and oxygen, is as follows:
In order to balance the reaction (the number of atoms of each element in the reaction are same on both the sides that is product and reactant), is multiplied by 3 in the reactant side and is multiplied by 2 and is multiplied by 3 on product side.
So, the balanced reaction is:
From the balanced reaction it is clear that 1 mole of reacts with 3 moles of to give 2 moles of and 3 moles of .
Since, 1 mole = molecules (Avogadro's number)
So,
Number of molecules of = molecules.
Number of molecules of = molecules.
Number of molecules of = molecules.
Number of molecules of = molecules.
Answer : The number of molecules of are 2, 3, 1 and 3 respectively.
Explanation :
The given balanced chemical reaction is,
Balanced chemical reaction is the reaction in which the number of atoms of an individual elements present on reactant side must be equal to the product side.
The species present on the left side of the right arrow is the reactant and the species present on the right side of the right arrow is the product.
From the balanced chemical reaction, we conclude that there are 1 molecule of , 3 molecules of , 2 molecules of and 3 molecules of .
Answer:
is a product of a condensation reaction.
Explanation:
In a condensation reaction, two molecules are combined to produced a large molecules along with removal of a water molecule.
For an example, let's consider aldol condensation reaction.
In aldol condensation reaction, an enolate anion reacts and combines with an aldehyde or ketone molecule follwed by dehydration. In that dehydration step , gets removed and an unsaturated carbonyl product is formed.
Usually, are produced as a by product of a decomposition reaction.
Answer:
group # = # valence electrons
group 2= 2 valence electrons
Explanation:
Mg is in group #2 and subsequently has 2 valence electrons (electrons on the outermost shell)
(2) 2 days (4) 4 days
Unstable heavy atoms will undergo radioactive decay to produce stable species. The half life time of the isotope which undergone a decay of 75 mg in 32 days is 18 days.
The half life time of a radioactive sample is the time taken to reduce it to half of the initial amount by decay.
The heavy unstable material have very short half life and they will easily undergoes radioactive decay by emitting certain radiation.
Radioactive decay is a firs order reaction and have the equation to find the radioactive constant as follows:
Where, t is the time of decay and Ni and Nt be the initial and final amount respectively.
It is given that 5 mg is remaining out of 80 mg after 32 days. Thus the radioactive constant is calculated as follows:
Now the half life time of the decay is calculated as below:
t(1/2) = 0.693 /decay constant
= 0.693/0.0376
= 18 days
Therefore, the half life time of the isotope which undergone a decay of 75 mg in 32 days is 18 days.
To find more about radioactive decay, refer the link below:
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