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vitfil [10]
3 years ago
11

PLEASE HELP!!

Chemistry
2 answers:
ivann1987 [24]3 years ago
5 0
The half-life of a radioactive substance describes the amount of time required for half of that radioactive substance to decay into a different form.

In this situation, 100 grams decays into 12.5 grams over the course of 8 hours. We have half lives that look like this -

100 grams - 50 grams (1) - 25 grams (2) - 12.5 grams (3)

three half lives have passed since the start over the course of eight hours, so:

8 hours/3 half-lives = ~2.667 hours per half-life

The half-life of this substance is approximately 2.667 hours.

Hope this helps!
omeli [17]3 years ago
3 0

Answer:

8/3 hours

Explanation:

12.5/100=1/8, 1/8*2=2/8=1/4 1/4*2=1/2 1/2*2 = 1 (whole)

we multiplyed 1/8 by two three times to get 1 so 8/3 hours is the answer

by the way i'm in 6th grade

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A system fitted with a piston expands when it absorbs 53.1 ) of heat from the surroundings. The piston is working against a pres
Hoochie [10]

Answer:

d. 60.8 L

Explanation:

Step 1: Given data

  • Heat absorbed (Q): 53.1 J
  • External pressure (P): 0.677 atm
  • Final volume (V2): 63.2 L
  • Change in the internal energy (ΔU): -108.3 J

Step 2: Calculate the work (W) done by the system

We will use the following expression.

ΔU = Q + W

W = ΔU - Q

W = -108.3 J - 53.1 J = -161.4 J

Step 3: Convert W to atm.L

We will use the conversion factor 1 atm.L = 101.325 J.

-161.4 J ×  1 atm.L/101.325 J = -1.593 atm.L

Step 4: Calculate the initial volume

First, we will use the following expression.

W = - P × ΔV

ΔV = - W / P

ΔV = - 1.593 atm.L / 0.677 atm = 2.35 L

The initial volume is:

V2 = V1 + ΔV

V1 = V2 - ΔV

V1 = 63.2 L - 2.35 L = 60.8 L

7 0
3 years ago
1. please answer i really need your help
elixir [45]

Answer:

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Explanation:

6 0
3 years ago
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Define saturated and unsaturated fats​
Sphinxa [80]

Answer:

<h3><u>Saturated and unsaturated</u>:-</h3>

Are a form of fat in which all or most of the fatty acid chains are single bonds. Glycerol and fatty acids are the two types of smaller molecules that make up fat.

<h3><u>Saturated fat is found in:</u></h3>
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  • sausages
  • cheese
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<h3><u>Examples of unsaturated fats:- </u></h3>
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hope it helps...

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Yuliya22 [10]

Answer: it’s a I believe

Explanation: protons are smaller then atoms which means they have less mass

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Answer:

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3 years ago
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