A change of one unit on the pH scale represents a change in the concentration of hydrogen ions by a factor of 10, a change in two units represents a change in the concentration of hydrogen ions by a factor of 100. Thus, small changes in pH represent large changes in the concentrations of hydrogen ions.
1 pound of coffee is said to yield 50 cups of coffee
So we need to find the pounds of coffee beans required to produce 250 cups
so if 50 cups need 1 pound of coffee beans
therefore 250 cups need - 1/50 x 250 = 5 pounds of coffee beans
since we have to find the amount of coffee beans needed in kg, we have to convert pounds to kg
1 pound = 0.45 kg
So if 1 pound is equivalent to 0.45 kg
then 5 pounds are equivalent to - 0.45 kg/pound x 5 pounds = 2.25 kg
therefore 2.25 kg of coffee beans are required
An open system is
when there is a transfer of energy and matter with its surroundings.
A closed system is
where there is a transfer of energy, may it be heat or work, but not matter
with its surroundings.
An isolated system
is where there is no transfer of energy or matter with its surroundings.
Answer:
-1,300 kJ
I don't want to explain it brainly AAAAA