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uranmaximum [27]

2 years ago

14

Analysis

1 answer:

Karolina [17]2 years ago

6 0

The properties of substances can be used to put the into groups.

<h3>Grouping of substances</h3>

In chemistry, it is often necessary to put substances into groups based on similarity in their properties. This is what led to the idea of a periodic table of elements.

Similarly, when we have unknown substances, we can group them according to the similarities in their properties.

Learn more about properties of substances: brainly.com/question/19886211

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An Asteroid is smaller than a planet but larger than a meteoroid? True or false pls no files or links they DO NOT WORK!!!!

velikii [3]

Answer:

true astroids are in space and are bigger than meteorites but smaller than planets, meteorites which are asteroids after landing on earth and losing most of its mass on its way

4 0

2 years ago

Science 5.13 unit 5 PLZZZ HELPPPP 99 point

sergey [27]

was is your question on it and what grade level are you?

8 0

3 years ago

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While exploring a coal mine, scientists found plant fossils in the ceiling of the mine which had been preserved by an earthquake

ale4655 [162]

Answer:

11552.45 years

Explanation:

Given that:

Half life = 5730 years

$t_{1/2}=\frac{\ln2}{k}$

Where, k is rate constant

So,

$k=\frac{\ln2}{t_{1/2}}$

$k=\frac{\ln2}{5730}\ years^{-1}$

The rate constant, k = 0.00012 years⁻¹

Using integrated rate law for first order kinetics as:

$[A_t]=[A_0]e^{-kt}$

Where,

$[A_t]$ is the concentration at time t

$[A_0]$ is the initial concentration

Given that:

The rate constant, k = 0.00012 years⁻¹

Initial concentration $[A_0]$ = 160.0 counts/min

Final concentration $[A_t]$ = 40.0 counts/min

Time = ?

Applying in the above equation, we get that:-

$40.0=160.0e^{-0.00012\times t}$

$e^{-0.00012t}=\frac{1}{4}$

$-0.00012t=\ln \left(\frac{1}{4}\right)$

$t=11552.45\ years$

7 0

3 years ago

Be sure to answer all parts. Calculate the pH of the following two buffer solutions: (a) 1.4 M CH3COONa/1.6 M CH3COOH. (b) 0.1 M

aalyn [17]

Answer:

a) pH = 4.68 (more effective)

b) pH =4.44.

Explanation:

The pH of buffer solution is obtained by Henderson Hassalbalch's equation.

The equation is:

$pH =pKa +log\frac{[salt]}{[acid]}$

a) pKa of acetic acid = 4.74

[salt] = [CH₃COONa] = 1.4 M

[acid] = [CH₃COOH] = 1.6 M

$pH = 4.74 + log \frac{1.4}{1.6}= 4.68$

This is more effective as there is very less difference in the concentration of salt and acid.

b) pKa of acetic acid = 4.74

[salt] = [CH₃COONa] = 0.1 M

[acid] = [CH₃COOH] = 0.2 M

$pH = 4.74 + log \frac{0.1}{0.2}= 4.44$

3 0

3 years ago

In the reaction Mg(s) + 2HCl(aq) → H2(g) + MgCl2(aq), how many moles of hydrogen gas will be produced from 250.0 milliliters of

satela [25.4K]

Mg + 2HCl = H₂ + MgCl₂

n(HCl)=c(HCl)v(HCl)

n(H₂)=n(HCl)/2=c(HCl)v(HCl)/2

n(H₂)=3.0mol/L*0.2500L/2=0.375 mol≈0.38 mol

5 0

3 years ago

Read 2 more answers