Answer:
Acetylene: -1,256 kJ/mol
Ethanol: -1,277 kJ/mol
The combustion of 0.25 mol of an unknown organic compound results in the release of 320 kJ of energy. Which of the compounds in the table could be the unknown compound?- Answer: Ethanol
Atomic mass Ni = 58.69 a.m.u
58.69 g ----------------- 6.02x10²³ atoms
?? g --------------------- 7.5x10¹⁵ atoms
58.69x (7.5x10¹⁵) / 6.02x10²³
=> 7.31x10⁻⁷ g
When we can get the Kinetic energy from this formula KE= 1/2 M V^2and we can get the potential energy from this formula PE = M g H
we can set that the kinetic energy at the bottom of the fall equals the potential energy at the top so, KE = PE
1/2 MV^2 = M g H
1/2 V^2 = g H
when V is the velocity, g is an acceleration of gravitational force (9.8 m^2/s) and H is the height of the fall (8 m).
∴ v^2 = 2 * 9.8 * 8 = 156.8
∴ v= √156.8 = 12.5 m/s
Answer is: <span>Mutations sometimes improve the chances of survival for a plant.
</span>Mutations are very important because they change <span>variability in populations and in that way enable evolutionary change.
</span>There are three types of mutations:
1) good or advantageous mutations - <span> improve the chances of survival for a plant.
2) </span>bad or deleterious - decrease the chances of survival for a plant.
3) neutral - not affect he chances of survival for a plant.
Answer : The number placed in front of 
should be, three (3).
Explanation :
Balanced chemical reaction : It is defined as the number of atoms of individual elements present on reactant side must be equal to the product side.
The given unbalanced chemical reaction is,
This chemical reaction is an unbalanced reaction because in this reaction, the number of atoms of chloride and sulfate ion are not balanced.
In order to balanced the chemical reaction, the coefficient 3 is put before the , the coefficient 2 is put before the 
and the coefficient 3 is put before the 
.
Thus, the balanced chemical reaction will be,
Therefore, the number placed in front of should be, three (3).
