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3 years ago

Please Help I will reward brainliest

Chemistry

2 answers:

8_murik_8 [283]3 years ago

7 0

I think it is "Known".

Radioactive decay is measured using a formula where the half-life of an isotope is the time it takes for the original nuclei to decay half of its original amount.

Alina [70]3 years ago

3 0

Base in what I found online it would be unpredictable . Hope that helps!

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An ethylene gas torch requires 300 L of gas at 0.8 atm. What will be the pressure of the gas if ethylene is supplied by a 200.0

Vlad [161]

Answer:

1.2 atm

Explanation:

Given data

Volume of the gas in the tank (V₁): 200.0 L

Pressure of ethylene gas in the tank (P₁): ?

Volume of the gas in the torch (V₂): 300 L

Pressure of the gas in the torch (P₂): 0.8 atm

If we consider ethylene gas to be an ideal gas, we can find the pressure of ethylene gas in the tank using Boyle's law.

$P_1 \times V_1 = P_2 \times V_2\\P_1 = \frac{P_2 \times V_2}{V_1} = \frac{0.8atm \times 300L}{200.0L} = 1.2 atm$

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3 years ago

In order to reduce the exposure to organic solvents like turpentine, some art instructors recommend the students clean brushes a

kykrilka [37]

Generally speaking, organic molecules tend to dissolve in solvents that have similar physical properties. A good rule of thumb is that "like dissolves like". Meaning, polar compounds can dissolve polar compounds and nonpolar compounds can dissolve nonpolar compounds.

To apply this to the current problem, we are told that the brushes are being cleaned with vegetable oil or mineral oil. In this case, the oils are used as solvents. In order for these solvents to be effective, the compounds they are trying to dissolve must be similar in structure and properties to other oils. Therefore, vegetable oil or mineral oil will be most effective in removing oil-based paints, as these will have the similar properties needed to dissolve in the oil solvents.

6 0

3 years ago

An example of a substance that can be decomposed by a chemical change is:

Savatey [412]

The answer is iron..

7 0

4 years ago

Read 2 more answers

Suppose the half-life is 9.0 s for a first order reaction and the reactant concentration is 0.0741 M 50.7 s after the reaction s

bazaltina [42]

Answer: The time taken by the reaction is 84.5 seconds

Explanation:

The equation used to calculate half life for first order kinetics:

$k=\frac{0.693}{t_{1/2}}$

where,

$t_{1/2}$ = half-life of the reaction = 9.0 s

k = rate constant = ?

Putting values in above equation, we get:

$k=\frac{0.693}{9}=0.077s^{-1}$

Rate law expression for first order kinetics is given by the equation:

$k=\frac{2.303}{t}\log\frac{[A_o]}{[A]}$ ......(1)

where,

k = rate constant = $0.077s^{-1}$

t = time taken for decay process = 50.7 sec

$[A_o]$ = initial amount of the reactant = ?

[A] = amount left after decay process = 0.0741 M

Putting values in equation 1, we get:

$0.077=\frac{2.303}{50.7}\log\frac{[A_o]}{0.0741}$

$[A_o]=3.67M$

Now, calculating the time taken by using equation 1:

$[A]=0.0055M$

$k=0.077s^{-1}$

$[A_o]=3.67M$

Putting values in equation 1, we get:

$0.077=\frac{2.303}{t}\log\frac{3.67}{0.0055}\\\\t=84.5s$

Hence, the time taken by the reaction is 84.5 seconds

6 0

3 years ago

How is primary selection different from secondary succession?

PIT_PIT [208]

Answer:

Explanation:

Primary and secondary succession occur after both human and natural events that cause drastic change in the makeup of an area. Primary succession occurs in areas where there is no soil and secondary succession occurs in areas where there is soil.

In primary succession, newly exposed or newly formed rock is colonized by living things for the first time. In secondary succession, an area previously occupied by living things is disturbed—disrupted—then recolonized following the disturbance.

Hope this helped :)

-Akito

8 0

3 years ago