1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Bad White [126]
3 years ago
14

A student is performing a titration to determine the concentration of a 20.0 mL sample of hydrochloric acid. What did the studen

t determine the concentration of the HCl to be if the end point was reached after 50.0 mL of 0.1 M NaOH was added.
Chemistry
1 answer:
irakobra [83]3 years ago
8 0

Answer:

0.25M HCl

Explanation:

The reaction of HCl with NaOH is:

HCl + NaOH ⇄ H₂O + NaCl

<em>Where 1 mole of HCl reacts per mole of NaOH</em>

The end point was reached when the student added:

0.0500L × (0.1mol / L) = 0.00500 moles of NaOH

As 1 mole of HCl reacted per mole of NaOH, moles of HCl present are:

<em>0.00500 moles HCl</em>

The volume of the sample of hydrochloric acid was 20.0mL = 0.0200L, and concentration of the sample is:

0.00500 mol HCl / 0.0200L = <em>0.25M HCl</em>

You might be interested in
HELP ASAP<br> In which reaction are the atoms of elements rearranged?
hammer [34]

Answer:

C. Explain ONE way in which the USA & USSR competed against each other during the Cold

War in the Post-World War Two period (c. 1945-present)

HURRY

Dr. Khan works for the marketing department of a company that manufactures mechanical toy dogs. Dr. Khan has been asked to assess the effectiveness of a new advertising campaign that is designed to be most persuasive to people with a certain personality profile. She brought four groups of participants to the lab to watch the video advertisements and to measure the likelihood that they would purchase the toy, both before and after watching the ad. The results of Dr. Khan’s study are presented below.

Part A

Explain how each of the following concepts applies to Dr. Khan’s research.

Survey

Dependent variable

Big Five theory of personality

Part B

Explain the limitations of Dr. Khan’s study based on the research method used.

Explain what Dr. Khan’s research hypothesis most likely was.

Part C

Use the graph to answer the following questions.

How did the trait of agreeableness affect how people responded to the new ad campaign?

How did the trait of conscientiousness affect how people responded to the new ad campaign?

5 0
3 years ago
Read 2 more answers
The heat of combustion of ethane is -337.0kcal at 25 degrees celsius. what is the heat of the reaction when 3g of ethane is burn
Ghella [55]

Answer:

Q = -33.6kcal .

Explanation:

Hello there!

In this case, according to the equation for the calculation of the total heat of reaction when a fixed mass of a fuel like ethane is burnt, we can write:

Q=n*\Delta _cH

Whereas n stands for the moles and the other term for the enthalpy of combustion. Thus, for the required total heat of reaction, we first compute the moles of ethane in 3 g as shown below:

n=3g*\frac{1mol}{30.08g}=0.1mol

Next, we understand that -337.0kcal is the heat released by the combustion of 1 mole of ethane, therefore, to compute Q, we proceed as follows:

Q=0.1mol*-337.0\frac{kcal}{mol}\\\\Q=-33.6kcal

Best regards!

8 0
3 years ago
What is the concentration if 20 grams of NaOH was dissolved in enough water to make a 250 mL NaOH solution?
gizmo_the_mogwai [7]

Answer: 1 molar NaOH contains 40 grams of NaOH per every liter of water

Explanation:

so 2 M NaOH contains twice that amount, ie. 80 grams per liter. Then, ine 250 ml of weater, there should be 80/4 = 20 grams of solid NaOH dissolved.

3 0
3 years ago
In the laboratory you dissolve 15.9 g of barium chloride in a volumetric flask and add water to a total volume of 375 ml. what i
ASHA 777 [7]
<span>There are a number of ways to express concentration of a solution. This includes molarity. Molarity is expressed as the number of moles of solute per volume of the solution. So, we calculate as follows:

Molarity =  15.9 g BaCl2 ( 1 mol / 208.23 g ) / .375 L = 0.204 mol / L</span>
5 0
3 years ago
In a fluorine atom, on which energy level are the valence electrons found?
aivan3 [116]

Answer:

second energy level

Explanation:

Valence electrons are those electrons which are present in outer most orbital of the atom.

This can be easily found through the electronic configuration of atom.

Electronic configuration of F:

F₉ = 1s² 2s² 2p⁵

We can see that the valence electrons are present in second energy level of F atom.

There are seven valence electrons of fluorine.

It is called halogens.

Halogens are very reactive these elements can not be found free in nature. Their boiling points also increases down the group which changes their physical states. i.e fluorine is gas while iodine is solid.

Fluorine:

1. it is yellow in color.

2. it is flammable gas.

3. it is highly corrosive.

4. fluorine has pungent smell.

5. its reactions with all other elements are very vigorous except neon, oxygen, krypton and helium.  

6 0
3 years ago
Other questions:
  • A compound or material formed by a chemical reaction is known as the of that reaction.
    6·1 answer
  • A compound contains only nitrogen and oxygen and is 30.5% nitrogen by mass. A gaseous sample of the compound has a density of 3.
    11·1 answer
  • Use Q = mcAT
    14·1 answer
  • A sample of lead has a density of 11.3 g/cm3 and a mass of 123 grams, what is the volume of the sample?
    8·1 answer
  • Para formar bronce, se mezclan 150g de cobre a 1100°C y 35g de estaño a 560°C. Determine la temperatura final del sistema.
    12·1 answer
  • PLEASE HELP, this assignment is worth 45 points and i dont have any free time to finish it
    11·2 answers
  • What is the chem formula for chromium (V) chloride?
    13·1 answer
  • This element has 80 electrons and is considered a transitional element. What am I?
    13·1 answer
  • Spindle fibers pull omologous pairs to ends of the cell 4 haploid daughter cells from
    11·1 answer
  • What is an ion and how does it form? What are the two types of ions
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!