Answer:
Zr. You should be able to see it on a periodic table.
Explanation:
There are 3 possible ways of determining pH.
1. A pH meter, 2. Litmus paper/ pH test strips or 3. Titrations.
1. A pH meter works by sending a small electric current through the solution. An electrical current can only be created if there are free-moving particles such as H+ ions from an acid or OH- ions from a base. The pH meter can determine the pH by how high the conductivity is.
2. Litmus Paper or pH test strips are strips that turn a specific colour under a specific pH. This colour can then be compared to a colour chart which will tell you the pH. The downfall of this method is that the red ink will stain the strip and you will be unable to get an accurate reading.
3. A titration is the best method, if done properly, for determining pH.
Answer:
13.3 %
Explanation:
Percent by mass indicates the mass of solute in 100g of solution.
We must know the solution's mass:
Solution's mass = Solute mass + solvent mass
Solution's mass = 10 g + 65 g = 75 g
Percent by mass = (10 g / 75 g).100 = 13.3 %
Otherwise, we can make a rule of three:
In 75 g of solution we have 10 g of solute
In 100 g of solution we must have (100 . 10) /75 = 13.3 %
You’ll need to set up a convention from moles over atoms to atoms over moles
Answer:
The correct answer is 783 kg.
Explanation:
To solve this problem, we first must simply add all three values together. We can perform this operation because all three values have the same units of kilograms.
When we add, we get:
258.3 + 271.23 + 253 = 782.53 kg
However, this answer does not have the correct number of significant digits. When adding and subtracting values, we round our final answer to the least amount of decimal places of the numbers we were adding. In this case, that is 0 decimal places, because 253 doesn’t have a decimal place.
Therefore, we should round 782.53 to the ones place. Since the next number is a 5, we round up.
This gives us 783 kg, which is our final answer.
Hope this helps!
