All categories

2 years ago

Help for this practice work

Chemistry

1 answer:

allochka39001 [22]2 years ago

8 0

Answer:

It's the third option.

Explanation:

In order for the chemical equation to be correctly it needs the same number of atoms of each element on both sides of the equal sign

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Which of the following statements is not correct?

Lilit [14]

Answer:

It's 4.1 moles Li2O = 94 g on Odyssey ware

8 0

2 years ago

Read 2 more answers

DIA [1.3K]

V_1=49.8mL
T_1=18°C=291K
T_2=83°C=356K

Using Charles law

$\\ \sf\longmapsto V_1T_2=V_2T_1$

$\\ \sf\longmapsto V_2=V_1T_2\div T_1$

$\\ \sf\longmapsto V_2=\dfrac{49.8(356)}{291}$

$\\ \sf\longmapsto V_2=\dfrac{17728.8}{291}$

$\\ \sf\longmapsto V_2=60.9mL$

5 0

2 years ago

A monoprotic weak acid when dissolved in water is 0.66% dissociated and produces a solution with a pH of 3.04. Calculate the Ka

raketka [301]

Answer:

Ka = 6.02x10⁻⁶

Explanation:

The equilibrium that takes place is:

HA ⇄ H⁺ + A⁻

Ka = [H⁺][A⁻]/[HA]

We calculate [H⁺] from the pH:

pH = -log[H⁺]

[H⁺] = $10^{-pH}$

[H⁺] = 9.12x10⁻⁴ M

Keep in mind that [H⁺]=[A⁻].

As for [HA], we know the acid is 0.66% dissociated, in other words:

[HA] * 0.66/100 = [H⁺]

We calculate [HA]:

[HA] = 0.138 M

Finally we calculate the Ka:

Ka = $\frac{[9.12x10^{-4}]*[9.12x10^{-4}]}{[0.138]}$ = 6.02x10⁻⁶

3 0

2 years ago

What is equal to the number of particles in 36 grams of carbon-12?

HACTEHA [7]

Answer:

3 moles

Explanation:

To solve this problem we will use the Avogadro numbers.

The number 6.022×10²³ is called Avogadro number and it is the number of atoms, ions or molecules in one mole of substance. According to this,

1.008 g of hydrogen = 1 mole = 6.022×10²³ atoms.

18 g water = 1 mole = 6.022×10²³ molecules

we are given 36 g of C-12. So,

12 g of C-12 = 1 mole

24 g of C-12 = 2 mole

36 g of C-12 = 3 mole

So 3 moles of C-12 equals to the number of particles in 36 g of C-12.

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2 years ago

Which describes how technology has changed society?

Anton [14]

Answer:

B. People live longer than they used to

Explanation:

None of the other answers are correct.

7 0

2 years ago