All categories

3 years ago

Help me please :3 :3 :3 ;3

Chemistry

2 answers:

tester [92]3 years ago

7 0

I think the correct answer is b

bekas [8.4K]3 years ago

6 0

I think the correct answer would be B) Suggestion 1

You might be interested in

What is the energy of a photon of green light with a frequency of 5.50 x 101^4 Hz?

Minchanka [31]

I didn't know if you meant to the power of 14 but if you did here your answer:
3.64 x 10^-19
(you just multiply the frequency by Planck's constant= 6.63 × 10^–34)

8 0

4 years ago

When a student mixes 50 mL of 1.0 M HCl and 50 mL of 1.0 M NaOH in a coffee-cup calorimeter, the temperature of the resultant so

zmey [24]

Answer: 54.4 kJ/mol

Explanation:

First we have to calculate the moles of HCl and NaOH.

$\text{Moles of HCl}=\text{Concentration of HCl}\times \text{Volume of solution}=1.0M\times 0.05=0.05mole$

$\text{Moles of NaOH}=\text{Concentration of NaOH}\times \text{Volume of solution}=1.0\times 0.05L=0.05mole$

The balanced chemical reaction will be,

$HCl+NaOH\rightarrow NaCl+H_2O$

From the balanced reaction we conclude that,

As, 1 mole of HCl neutralizes by 1 mole of NaOH

So, 0.05 mole of HCl neutralizes by 0.05 mole of NaOH

Thus, the number of neutralized moles = 0.05 mole

Now we have to calculate the mass of water:

As we know that the density of water is 1 g/ml. So, the mass of water will be:

The volume of water = $50ml+50ml=100ml$

$\text{Mass of water}=\text{Density of water}\times \text{Volume of water}=1g/ml\times 100ml=100g$

Now we have to calculate the heat absorbed during the reaction.

$q=m\times c\times (T_{final}-T_{initial})$

where,

q = heat absorbed = ?

$c$ = specific heat of water = $4.18J/g^oC$

m = mass of water = 100 g

$T_{final}$ = final temperature of water = $27.5^0C$

$T_{initial}$ = initial temperature of metal = $21.0^0C$

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

$q=100g\times 4.18J/g^oC\times (27.5-21.0)^0C$

$q=2719.6J=2.72kJ$

Thus, the heat released during the neutralization = 2.72 KJ

Now we have to calculate the enthalpy of neutralization per mole of $HCl$ :

0.05 moles of $HCl$ releases heat = 2.72 KJ

1 mole of $HCl$ releases heat = $\frac{2.72}{0.05}\times 1=54.4KJ$

Thus the enthalpy change for the reaction in kJ per mol of HCl is 54.4 kJ

6 0

3 years ago

Read 2 more answers

Pick a "for every" statement about copper and silver nitrate for this reaction.

maxonik [38]

From the equation of the reaction; for every 1 mole of copper, the reaction uses 2 moles of silver nitrate.

<h3>What is a reaction?</h3>

A chemical reaction involves the transformation of one chemical specie into another. The reaction is not shown here hence the question is incomplete.

However, the reaction should be of the sort; Cu + 2AgNO3 ---> Cu(NO3)2 + Cu. Thus, for every 1 mole of copper, the reaction uses 2 moles of silver nitrate.

Learn more about chemical reaction: brainly.com/question/6876669

8 0

2 years ago

2. Use the Henderson-Hasselbalch equation to estimate the pH of a buffer solution that is composed of 20 mL of 10 M sodium forma

Mkey [24]

Answer:

pH of buffer =4.75

Explanation:

The pH of buffer solution is calculated using Henderson Hassalbalch's equation:

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

Given:

pKa = 3.75

concentration of acid = concentration of formic acid = 1 M

concentration of salt = concentration of sodium formate = 10 M

$pH=3.75+log[\frac{10}{1}]=3.75+1=4.75$

pH of buffer =4.75

7 0

3 years ago

Something that causes a response in an organism is called a(n) _____.

fomenos

A Stimulus is the answer

7 0

3 years ago