Answer:
b. Heat flows from the surroundings to the system and the temperature of the water decreases.
Explanation:
The laws of thermodynamics lets us know that energy is neither created nor destroyed but can be converted from one form to another. Also, energy transfer does accompany chemical reactions in the form of heat.
For an endothermic reaction, heat is absorbed by the system from the surroundings. This leads to a drop in the temperature of the surroundings as energy is removed.
This implies that the water temperature decreases.
Answer:
Explanation:
Volume is defined as the space occupied by an object or substance irrespective of its state of matter.The conversion used from millimeter to liter is:
1 milliiliter = 0.001 L
Therefore, we can convert the volume of sample from 2.5 ml in liters as follows.
2.5 ml in liters = 2.5ml x 0.001 L/1ml
= 0.0025 L
Thus, we can conclude that the volume of given sample in liter is 0.0025 L
Hope this helps! :)
Unit of M is also mole/L, where mole is the moles of solute and L is the volume of the solution. The latter is given: 158 mL or 0.158 L. So we need to find out the moles of NH4Br.
Moles of NH4Br = Mass of NH4Br/molar mass of NH4Br = 17.0g/(14+1*4+79.9)g/mol = 0.1736 mole.
So, the molarity of the solution = 0.1736mole/0.158L = 1.10 mole/L = 1.10 M
Answer:
[OH-] = 1.0 x 10-10 M
Explanation:
The acidity of a solution can be determined directly from the concentration of the hydrogen ions and indirectly from the concentrations of the hydroxide ions.
Generally, for a neutral solution we have;
[H3O+] = [OH-] = 1.0 x 10-7 M
For an acidic solution;
[H3O+] > 1.0 x 10-7 M
[OH-] < 1.0 x 10-7 M
Comparing the options the correct option is;
[OH-] = 1.0 x 10-10 M
It is correct, next time re-check your answer and don't second guess yourself. ;3