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3 years ago

Do you believe the research subjects in the original study were appropriate for this experiment

Chemistry

2 answers:

olga55 [171]3 years ago

5 0

Umm......in what study?

ioda3 years ago

4 0

Fgdgdfgdfgdfgdfgfdgfsdasffglkjhuifgnufgu

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Non-renewable energy is often called?

DIA [1.3K]

Answer:

It is also called a finite resource

Explanation:

5 0

3 years ago

Rank these acids according to their expected pKa values.ClCH2COOHClCH2CH2COOHCH3CH2COOHCl2CHCOOHIn order of highest pka to lowes

Ilia_Sergeevich [38]

Answer:

CH₃CH₂CH₂COOH > CH₃CH₂COOH > ClCH₂CH₂COOH > ClCH₂COOH

Explanation:

Electron-withdrawing groups (EWGs) increase acidity by inductive removal of electrons from the carboxyl group.

Electron-donating groups (EDGs) decrease acidity by inductive donation of electrons to the carboxyl group.

The closer the substituent is to the carboxyl group, the greater is its effect.
The more substituents, the greater the effect.
The effect tails off rapidly and is almost zero after about three C-C bonds.

CH₃CH₂-CH₂COOH — EDG — weakest — pKₐ = 4.82

CH₃-CH₂COOH — reference — pKₐ = 4.75

ClCH₂-CH₂COOH — EWG on β-carbon— stronger — pKₐ = 4.00

ClCH₂COOH — EWG on α-carbon — strongest — pKₐ = 2.87

6 0

2 years ago

Read 2 more answers

Help me in my this plzzz

eduard

Answer:

a is oxidation

b is reduction

c is reduction

d is oxidation

hope it helps you

8 0

3 years ago

Read 2 more answers

What is the mass in grams of 3x10 atoms of helium

Zepler [3.9K]

Answer:

here

Explanation:

What is the total mass of $$3.01 x 10^23$$ atoms of helium gas?

✓ Well $$"Avogadro's number"$$ of helium atoms has a mass of $$4.0*g$$. Explanation: And $$"Avogadro's number"$$

3 0

2 years ago

s) Suppose we now collect hydrogen gas, H2(g), over water at 21◦C in a vessel with total pressure of 743 Torr. If the hydrogen g

Elenna [48]

This is an incomplete question, here is a complete question.

Suppose we now collect hydrogen gas, H₂(g), over water at 21°C in a vessel with total pressure of 743 Torr. If the hydrogen gas is produced by the reaction of aluminum with hydrochloric acid:

$2Al(s)+6HCl(aq)\rightarrow 2AlCl_3(aq)+3H_2(g)$

what volume of hydrogen gas will be collected if 1.35 g Al(s) reacts with excess HCl(aq)? Express your answer in liters.

Answer : The volume of hydrogen gas that will be collected is 1.85 L

Explanation :

First we have to calculate the number of moles of aluminium.

Given mass of aluminium = 1.35 g

Molar mass of aluminium = 27 g/mol

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$

$\text{Moles of aluminium}=\frac{1.35g}{27g/mol}=0.05mol$

The given chemical reaction is:

$2Al(s)+6HCl(aq)\rightarrow 2AlCl_3(aq)+3H_2(g)$

As, hydrochloric acid is present in excess. So, it is considered as an excess reagent.

Thus, aluminium is a limiting reagent because it limits the formation of products.

By Stoichiometry of the reaction:

2 moles of aluminium produces 3 moles of hydrogen gas

So, 0.005 moles of aluminium will produce = $\frac{3}{2}\times 0.05=0.0750mol$ of hydrogen gas

Now we have to calculate the mass of helium gas by using ideal gas equation.

PV = nRT

where,

P = Pressure of hydrogen gas = 743 Torr

V = Volume of the helium gas = ?

n = number of moles of hydrogen gas = 0.075 mol

R = Gas constant = $62.364\text{ L Torr }mol^{-1}K^{-1}$

T = Temperature of hydrogen gas = $21^oC=[21+273]K=294K$

Now put all the given values in above equation, we get:

$743Torr\times V=0.075mol\times 62.364\text{ L Torr }mol^{-1}K^{-1}\times 294K\\\\V=1.85L$

Hence, the volume of hydrogen gas that will be collected is 1.85 L

8 0

3 years ago