When energy is needed in order for the reaction to happen, then that reaction is known as endotermic. When the reaction has as a result energy then it is exotermic. An example of an endotermic reaction would be photosynthesis, for an exotermic: combustion.
Ouestion no 10 answer is first and 11 is 3
Answer:
1. Density can be used to identify a substance
2. Density can be used to ascertain whether a substance will float in water.
Explanation:
The calculation of the density of a substance can be used to identify the substance. If the density of a substance is calculated accurately, and compared with a table of standard densities, then we can identify that substance.
Also, density determines whether an object will float or sink in water. If an object is less dense than water then it will float in water. If it is denser than water, then it will sink in water.
Answer:
3626.76dm³
Explanation:
Given parameters:
Number of moles of Nitrogen in tank = 17moles
Temperature of the gas = 34°C
Pressure on the gas = 12000Pa
Unkown:
Volume of the tank, V =?
Converting the parameters to workable units:
We take the temperature from °C to Kelvin
K = 273 + °C = 273 + 34 = 307k
Taking the pressure in Pa to atm:
101325Pa = 1atm
12000Pa = 0.118atm
Solution:
To solve this problem, we employ the use of the ideal gas equation. The ideal gas law combines three gas laws which are the Boyle's law, Charles's law and the Avogadro's law.
It is expressed as PV = nRT
The unknown is the Volume and we make it the subject of the formula
V =
Where R is called the gas constant and it is given as 0.082atmdm³mol⁻¹K⁻¹
Therefore V = = 3626.76dm³
Yes you do cause its more explanation to
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