27. Some forces require direct contact, while others, like gravity, act at a distance. Which of the following is NOT

how many electrons does chlorine need to gain to become an ion? will it become positively charged cation or negatively charged a

I am Lyosha [343]

One electron and it becomes negatively charged

6 0

2 years ago

Calculate the amount in grams of Na2CO3 needed in a reaction with HCl to produce 120g NaCl?

klemol [59]

The balanced chemical reaction is written as :

Na2CO3 + 2HCl === 2NaCl + H2O + CO2

We are given the amount of NaCl to be produced from the reaction. This will be the starting point for the calculations. We do as follows:

120 g NaCl ( 1 mol / 58.44 g) ( 1 mol Na2CO3 / 2 mol NaCl)( 105.99 g / 1 mol ) = 1108.82 g Na2CO3 needed

8 0

3 years ago

Under the gold standard, a country in balance-of-trade equilibrium earns income from exports that is equal to the money its resi

solong [7]

The answer is true.

Explanation:

The balance of trade is nothing but the country's exports minus the country's imports.

Exports means, what you produce in the country and sell it to other countries, whereas imports means what you get or buy from the other countries.

When you export more than you import, you have trade surplus .In that case the income from exports are more than the money spent. So you have a trade surplus.

When you import then you have a trade deficit or your income is low. Most of the countries want a trade surplus.

But when the Income from exports and the money spent on imports are the same , the situation is that of balance of trade equilibrium, where the income from exports is equal to the money its residents pay for the imports.

4 0

3 years ago

ENT

Vesna [10]

Answer:

law of independent assortment

7 0

3 years ago

You are asked to prepare 500 mL 0.300 M500 mL 0.300 M acetate buffer at pH 4.904.90 using only pure acetic acid ( MW=60.05 g/mol

defon

Answer:

You will need 9,0 g of acetic acid

Explanation:

The equilibrium acetate-acetic acid is:

CH₃COOH ⇄ CH₃COO⁻ + H⁺ pka = 4,76

Using Henderson-Hasselbalch you will obtain:

pH = pka + log₁₀ $\frac{[A^{-}]}{[HA]}$

Where HA is acetic acid and A⁻ is acetate ion

4,90 = 4,76 + log₁₀ $\frac{[A^{-}]}{[HA]}$

1,38 = $\frac{[A^{-}]}{[HA]}$ (1)

As acetate concentration is 0,300M:

0,300M = [HA] + [A⁻] (2)

Replacing (2) in (1):

[HA] = 0,126 M

And:

[A⁻] = 0,174 M

As you need to produce 500 mL:

0,5 L × 0,126 M = 0,063 moles of acetic acid

0,5 L × 0,174 M = 0,087 moles of acetate

To produce moles of acetate from acetic acid:

CH₃COOH + NaOH → CH₃COO⁻ + Na⁺ + H₂O

Thus, moles of acetate are equivalents to moles of NaOH and all acetates comes from acetic acid, thus:

0,087 moles of acetate + 0,063 moles of acetic acid ≡ 0,15 moles of acetic acid × $\frac{60,05 g}{1mol}$ = 9,0 g of acetic acid

I hope it helps!

5 0

3 years ago