Answer:
five half lives
Explanation:
Half-life is the time required for a quantity to reduce to half of its initial value.
How many half lives it would take to reach 3.13% form 100% of it's initial concentration:
100% - 50% : First Half life
50% - 25%: Second Half life
25% - 12.5%: Third Half life
12.5% - 6.25%: Fourth Half life
6.25% - 3.125%: Fifth Half life
This means it would take five half lives to get to 3.125% (≈ 3.13%) of it's original concentration.
Answer:
Demonstration 1 showed a chemical change because a new gaseous substance was formed, and demonstration 2 showed a physical change because liquid water became water vapor.
Explanation:
Chemical changes alter the chemical makeup of a subject, and a physical change only alters the appearance of a subject, not the chemical makeup.
In late 18th century, people wore rubber soled shoes called plimsolls, but they weren't the best sneakers. Around 1892, a US company named Keds started sneakers with a canvas top and rubber soles. By 1917, these were mass produced.
Answer:
Yes
Explanation:
We have been created by him therefore we would not have been created if there was no God.
