Answer: There are five signs of chemical change
- Color Change
- Production of an odor
- Change of Temperature
- Evolution of Gas (bubbles start to form)
- Precipitate (starts to form a solid)
When these signs start to form you know chemical change is at work.
Hope this helps :)
Answer:
[KBr] = 454.5 m
Explanation:
m is a sort of concentration that indicates the moles of solute which are contianed in 1kg of solvent.
In this case, the moles of solute are 0.25 moles.
Let's determine the mass of solvent in kg.
Density of heavy water, solvent, is 1.1 g/L and our volume is 0.5L.
1.1 g = mass of solvent / 0.5L, according to density.
mass of solvent = 0.5L . 1.1g/L = 0.55 g
We convert the mass to kg → 0.55 g . 1kg /1000g = 5.5×10⁻⁴ kg
m = mol/kg → 0.25 mol /5.5×10⁻⁴ kg = 454.5 m
<span>17.5 g
35 ppt stands for 35 parts per thousand. So let's convert that to a decimal number by taking 35 and dividing by 1000.
35/1000 = 0.035
Now multiply that number by the number of grams of seawater you have. So
0.035 * 500 g = 17.5 g
So you have 17.5 grams of salt when you have 500 grams of seawater.</span>
POH of a 0.0072 M=-lg(0.0072) = 2.1426675
