I don't know how to solve no 5 <br> And i really need it fast and in french

Of the 20 amino acids, how many amino acids are considered essential? why are they called essential?

Karo-lina-s [1.5K]

There are nine essential amino acids for humans (histadine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine) that must come from your … food.

5 0

4 years ago

What is definition "scientific question"?

Lemur [1.5K]

Answer:

A scientific question is basically a question that can lead to a hypothesis to help us figure out the observation in science. I hope this helps you

4 0

3 years ago

Read 2 more answers

Which of the following is a reasonable ground-state electron configuration?

Fittoniya [83]

Answer:

A ground state electron configuration follows the Aufbau Principle that states that electrons should be filled up in orbitals in increasing energy. In the given sequences, the right configuration is

1s2 2s2 2p6 3s2 3p6 4s2 3d8.

Explanation:

6 0

3 years ago

In boyle's law, the initial volume of a gas is 120 ml at 256 kpa. what will be the volume if the pressure increases to 385 kpa?

Vinil7 [7]

<h3>Answer:</h3>

79.8 ml

<h3>Explanation:</h3>

Boyle's law describes the relationship between pressure and volume when the temperature is constant. For this question, I will be rounding to significant figures.

Boyle's Formula

When describing the relationship between pressure and volume, the formula $\displaystyle P_{1} V_{1}= P_{2} V_{2}$ . In this formula, $P_{1}V_{1}$ is the initial pressure and volume. On the other side, $P_{2} V_{2}$ is final pressure and volume. So, to find a missing variable you must plug in the values you are given.

Final Volume

Remember when solving this question to remain constant in your units. When we plug in the values we know we are given:

$256kPa*120mL=385kPa*V_{2} mL$

Now, we can multiply the left side

$30720kPa*mL=385kPa*V_{2} mL$

Finally, we can divide by 385 to isolate the final volume

$79.8mL=V_{2}$

This gives the final volume of 79.8mL.

7 0

2 years ago

A 500.0-mL buffer solution is 0.100 M in HNO2 and 0.150 M in KNO2. Determine if each addition would exceed the capacity of the b

likoan [24]

Answer:

no one additions exceed the capacity of the buffer

Explanation:

given

Volume buffer = 500.0 mL = 0.5 L

mol HNO₂ = 0.5 L × 0.100 mol/L = 0.05 mol HNO₂

mol NO₂⁻ = 0.5 L × 0.150 mol/L = 0.075 mol NO₂⁻

solution

we know when any base more than 0.05 (HNO2) than exceed buffer capacity

and when any base more than 0.075 (KNO2) than exceed buffer capacity

when we add 250 mg NaOH (0.250 g)

than molar mass NaOH =40 g/mol

and mol NaOH = 0.250 g ÷ 40g/mol

mol NaOH = 0.00625 mol

0.00625 mol NaOH will be neutralized by 0.00625 mol HNO₂

so it would not exceed the capacity of the buffer.

and

when we add 350 mg KOH (0.350 g)

than molar mass KOH =56.10 g

and mol KOH = 0.350 g ÷ 56.10 g/mol

mol KOH = 0.0062 mol

here also capacity of the buffer will not be exceeded

and

now we add 1.25 g HBr

than molar mass HBr = 80.91 g/mol

and mol HBr = 1.25 g ÷ 80.91 g/mol

mol HBr = 0.015 mol

0.015 mol Hbr will neutralize 0.015 mol NO₂⁻

so the capacity will not be exceeded.

and

we add 1.35 g HI

molar mass HI = 127.91 g/mol

so mol HI = 1.35 g ÷ 127.91 g/mol

mol HI = 0.011 mol

capacity of the buffer will not be exceed

3 0

3 years ago

I don't know how to solve no 5 And i really need it fast and in french