Answer:
Phenol red indicator.
Explanation:
- Phenol red indicator is an organic dye which works as an indicator in the pH range (6.8 - 8.4) for acid-base reactions.
<em>The color in acidic solutions is yellow and in basic solution is red.</em>
Answer:
44.63g
Explanation:
First, let us calculate the number of mole of KBr in 1.50M KBr solution.
This is illustrated below:
Data obtained from the question include:
Volume of solution = 250mL = 250/1000 = 0.25L
Molarity of solution = 1.50M
Mole of solute (KBr) =.?
Molarity is simply mole of solute per unit litre of solution
Molarity = mole /Volume
Mole = Molarity x Volume
Mole of solute (KBr) = 1.50 x 0.25
Mole of solute (KBr) = 0.375 mole
Now, we calculate the mass of KBr needed to make the solution as follow:
Molar Mass of KBr = 39 + 80 = 119g/mol
Mole of KBr = 0.375 mole
Mass of KBr =?
Mass = number of mole x molar Mass
Mass of KBr = 0.375 x 119
Mass of KBr = 44.63g
Therefore, 44.63g of KBr is needed to make 250.0mL of 1.50 M potassium bromide (KBr) solution
Answer:
Rutherford's gold foil experiment showed that the atom is mostly empty space with a tiny, dense, positively-charged nucleus. Based on these results, Rutherford proposed the nuclear model of the atom.
Explanation:
Answer: The definition of periodic is something that is recurring at regular intervals, or happens from time to time. An example of periodic is a person's birthday happening once each year.
hope this helps y❣️
<span>Spontaneous reactions need to be discovered first. Also, if reagents are transferred to the other cups used in the tests, it could contaminate them, leading to different colors being seen and the test results being invalid. Doing the reagent tests last ensure that the cups and reagents are only used on the substances that they are intended to.</span>
