7. D. 668 joules
8. B. 3 grams
<h3>Further explanation</h3>
Given
2 grams of water
6768 joules of energy
Required
Energy
Mass of water
Solution
The heat to change the phase can be formulated :
Q = m.Lf (melting/freezing)
Q = m.Lv (vaporization/condensation)
Lf=latent heat of fusion
Lv=latent heat of vaporization
7. phase change (ice to water)⇒Heat of fusion water=334 J/g
Q = 2 g x 334 J/g
Q = 668 J
8. phase change(water to vapor)⇒heat of vaporization water=2260 J/g
6768 J = m x 2260 J/g
m = 3 g
The answer is Human behavior.
There are three carbon and 8 hydrogen present in propane molecule. The Lewis structure of propane is shown as:
Three molecules of such carbon atoms bound to eight molecules with hydrogen atoms make up the organic complex propane molecule.
It is known that carbon has 4 valence electrons and hydrogen has one valence electron. Carbon needs 4 extra electrons to complete its octet hence, it will share its electrons with with 4 hydrogen atom and complete its octet.
Carbon will be formed 4 bond . Three bond with hydrogen and one bond with carbon atom.
To know more about Lewis structure.
brainly.com/question/15837141
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Answer:
i. Atomic radius of an atom is defined as the total distance from the nucleus to the outermost shell of the atom.
On moving from left to right ( Mg, K) in a period, more and more electrons get added up in the same shell and the attraction between the last electron and nucleus increases, which results in the shrinkage of size of an atom. Thus, decreasing the atomic radii of the atom on moving towards right of the periodic table.
As moving from top to bottom, there is an addition of shell around the nucleus and the outermost shell gets far away from the nucleus and hence, the distance between the nucleus and outermost shell increases.
Thus the order of atomic radii is : Ca > Mg > K
ii. The energy required to remove the last valence electron from isolated gaseous atom (first ionization energy) increases as we move from left to right in a period. It decreases on moving from top to bottom.
Thus the order of first ionization energy is : K > Mg > Ca
iii. The chemical properties depend on the valence elctrons and as the elements Mg and Ca both have two valence electrons , they have same chemical properties.
Answer:
2:3
You'd need 33.3 moles of potassium chlorate, KClO3 , to produce that much oxygen. Notice that you have a 2:3. mole ratio between potassium chlorate and oxygen gas, which means that, regardless of how many moles of the former react, you'll always produce 3/2 times more moles of the latter.
Explanation:
