Exothermic change. Because the firework when it exploded, released energy in the form of light. In exothermic changes energy is released, and in endothermic changes energy is absorbed.
- This wouldn't be a physical change, but instead a chemical change. A clue that it is a chemical change is that energy was given off.
Answer:
b) 7
Explanation:
The pH of a solution produced by the neutralization reaction between 1M of H₂SO₄ and KOH with 1M is closest to 7.
pH is a standard for measuring the acidity and alkalinity of a solution. A solution that is acidic will have a pH less than 7, a neutral solution will have pH of 7 and a basic solution will have pH greater than 7.
What is a neutralization reaction?
- It is an acid-base reaction in which hydrogen and hydroxide ions combines to form water.
- Also a salt results from the combination of the other ions.
In this reaction a base simply neutralizes an acid and the solution becomes neutral before it goes into completion.
Therefore, a neutral solution will have pH of 7 or close to it.
Pretty much, if I were going to separate small solid particles, I could use like a piece of paper. I used some type of piece of paper when I was trying to separate some particles during science.
Answer:
The amount left after 49.2 years is 3mg.
Explanation:
Given data:
Half life of tritium = 12.3 years
Total mass pf tritium = 48.0 mg
Mass remain after 49.2 years = ?
Solution:
First of all we will calculate the number of half lives.
Number of half lives = T elapsed/ half life
Number of half lives = 49.2 years /12.3 years
Number of half lives = 4
Now we will calculate the amount left after 49.2 years.
At time zero 48.0 mg
At first half life = 48.0mg/2 = 24 mg
At second half life = 24mg/2 = 12 mg
At 3rd half life = 12 mg/2 = 6 mg
At 4th half life = 6mg/2 = 3mg
The amount left after 49.2 years is 3mg.