Answer:
177253.125hrs
Explanation:
Given parameters:
Number of hours spend per day on phone = 6.25hrs
Unknown:
Average hours pend by an average American if they lived for 77.7yrs
Solution:
Let us find the number of hours an average American spends on their phone per year;
there are 365days in a year
Number of hours = 365 x 6.25 = 2,281.25hrs
Now, if they lived for 77.7yrs;
They will spend = 77.7 x 2,281.25 = 177253.125hrs
Answer:
temporary changes are the changes which are there only for a short period if time.
Explanation:
generally temporary changes are reversible. permanent changes are the changes which remain for a longer time and are not reversible
Answer:
You never listed the options
Explanation:
A chemical reaction is a process that involves rearrangement of the molecular or ionic structure of a substance, as opposed to a change in physical form or a nuclear reaction.
Answer:
If the electronegativity difference between bonded atoms are too much high ionic bonds are formed if the electronegativity diference is 0.4 or less than 0.4 non polar covalnet bond formed the difference greater than 0.4 polar covalent bond formed.
Explanation:
Ionic bond:
It is the bond which is formed by the transfer of electron from one atom to the atom of another element.
Both bonded atoms have very large electronegativity difference. The atom with large electronegativity value accept the electron from other with smaller value of electronegativity.
For example:
Sodium chloride is ionic compound. The electronegativity of chlorine is 3.16 and for sodium is 0.93. There is large difference is present. That's why electron from sodium is transfer to the chlorine. Sodium becomes positive and chlorine becomes negative ion.
Covalent bond:
It is formed by the sharing of electron pair between bonded atoms.
The atom with larger electronegativity attract the electron pair more towards it self and becomes partial negative while the other atom becomes partial positive.
For example:
In water the electronegativity of oxygen is 3.44 and hydrogen is 2.2. That's why electron pair attracted more towards oxygen, thus oxygen becomes partial negative and hydrogen becomes partial positive.
Answer:
Explanation:
Among the most recent systems for the exploitation of geothermal energy, the most promising are the third generation ones, also called EGS (Enhanced Geothermal Systems). Their technology allows to dramatically improve energetic efficiency of both geothermal wells and dry rocks.
Present and Future of Geothermal Energy - Cividachttp://www.cividac.com › news › present-and-future-of-g...