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
aleksklad [387]
3 years ago
15

A teacher cut an apple into three wedges of the same size.She dipped one wedge in lemon juice, dipped another in water ,and left

one alone. Then she left the wedges on a paper towel on her desk. After 1 hour, only the wedge that had been dipped in lemon juice was still yellow. The other two wedges had turned brown.
Chemistry
1 answer:
jasenka [17]3 years ago
7 0
It’s national park and I have to do the same as I have to get some money drops and then we will have a lot to go back on and I get the same
You might be interested in
In his proposed model of the atom, J.J. Thomson imagined the atom contained _____.
lara [203]
<span>electrons and space filled with wispy positive charge I would love if I could get brainliest :)

</span>
6 0
3 years ago
Read 2 more answers
Chromium(III) oxide reacts with hydrogen sulfide (H2S) gas to form chromium(III) sulfide and water: Cr2O3(s) + 3H2S(g) → Cr2S3(s
Tpy6a [65]

Answer:

(a) 0.779 mol Cr₂O₃

(b) 118 g Cr₂O₃

Explanation:

Step 1: Convert 156 g Cr₂S₃ to moles

Cr Molar Mass - 52.00 g/mol × 2 = 104.00 g/mol

S Molar Mass - 32.07 g/mol × 3 = 96.21 g/mol

156 g Cr₂S₃ ÷ 200.21 g/mol = 0.779182 mol Cr₂S₃

Step 2: Find conversion from Cr₂S₃ to Cr₂O₃

1 mol Cr₂S₃ equals 1 mol Cr₂O₃

Step 3: Use Dimensional Analysis

0.779182 mol Cr₂S₃ · \frac{1 \hspace{2} mol \hspace{2} Cr_2O_3}{1 \hspace{2} mol \hspace{2} Cr_2S_3} = 0.779182 mol Cr₂O₃

0.779182 mol Cr₂O₃ ≈ 0.779 mol Cr₂O₃ (3 significant figures)

Step 4: Convert moles to grams

Cr Molar Mass - 52.00 g/mol × 2 = 104.00 g/mol

O Molar Mass - 16.00 g/mol × 3 = 48.00 g/mol

0.779182 mol Cr₂O₃ · 152.00 g/mol = 118.436 g Cr₂O₃

118.436 g Cr₂O₃ ≈ 118 g Cr₂O₃ (3 significant figures)

6 0
2 years ago
Which term describes a substance that increases the concentration of hydroxide ions in solution?
steposvetlana [31]
Arrhenius definition of a base

An Arrhenius base is a substance that increases the concentration of OH- ions when dissolved in water.
5 0
3 years ago
Read 2 more answers
The rate constant k for a certain reaction is measured at two different temperatures temperature 376.0 °c 4.8 x 108 280.0 °C 2.3
9966 [12]

Answer:

The activation energy for this reaction = 23 kJ/mol.

Explanation:

Using the expression,

\ln \dfrac{k_{1}}{k_{2}} =-\dfrac{E_{a}}{R} \left (\dfrac{1}{T_1}-\dfrac{1}{T_2} \right )

Where,

k_1\ is\ the\ rate\ constant\ at\ T_1

k_2\ is\ the\ rate\ constant\ at\ T_2

E_a is the activation energy

R is Gas constant having value = 8.314×10⁻³ kJ / K mol  

k_2=2.3\times 10^8

T_2=280\ ^0C  

The conversion of T( °C) to T(K) is shown below:

T(K) = T( °C) + 273.15  

So,  

T = (280 + 273.15) K = 553.15 K  

T_2=553.15\ K  

k_1=4.8\times 10^8  

T_1=376\ ^0C  

The conversion of T( °C) to T(K) is shown below:

T(K) = T( °C) + 273.15  

So,  

T = (376 + 273.15) K = 649.15 K  

T_1=649.15\ K  

So,  

\left(\ln \left(\:\frac{4.8\times \:\:\:10^8}{2.3\times \:\:\:10^8}\right)\right)\:=-\frac{E_a}{8.314\times \:10^{-3}\ kJ/mol.K}\times \:\left(\frac{1}{649.15\ K}-\frac{1}{553.15\ K}\right)

E_a=-\frac{10^{-3}\times \:8.314\ln \left(\frac{10^8\times \:4.8}{10^8\times \:2.3}\right)}{-\frac{96}{359077.3225}}\ kJ/mol

E_a=-\frac{\frac{8.314\ln \left(\frac{4.8}{2.3}\right)}{1000}}{-\frac{96}{359077.3225}}\ kJ/mol

E_a=22.87\ kJ/mol

<u>The activation energy for this reaction = 23 kJ/mol.</u>

6 0
3 years ago
Cu + 2AgNO3 → Cu(NO3)2 + 2Ag
Eva8 [605]

Answer:

m_{Ag}=135.8gAg

Y=88.4\%

Explanation:

Hello there!

In this case, according to the described chemical reaction, it is possible to compute the theoretical mass of silver as mass via the 1:2 mole ratio of copper to silver and their atomic mass in the periodic table, in order to perform the following stoichiometric setup:

m_{Ag}=40.gCu*\frac{1molCu}{63.55gCu}*\frac{2molAg}{1molCu}*\frac{107.87gAg}{1molAg}\\\\   m_{Ag}=135.8gAg

Next, given the actual yield of 120 g, we compute the percent yield via:

Y=\frac{120g}{135.8g}*100\%\\\\Y=88.4\%

Regards!

4 0
3 years ago
Other questions:
  • What is the chemical formula for flint
    11·1 answer
  • The si unit for measuring acceleration is?
    8·2 answers
  • ) Any gas exerts a pressure against its surroundings. For example, if you put more gas in a balloon, it exerts more pressure and
    10·1 answer
  • Definition of metallurgy
    12·2 answers
  • Of the following, which most likely involves a chemical reaction?
    12·1 answer
  • What element is Column 1, period 3
    12·1 answer
  • What is the name of the molecule shown below?
    8·1 answer
  • 7.895 g + 3.4 g round to the correct number significant figures
    7·1 answer
  • When washing items in the detergent solution when do you replace the water.
    13·1 answer
  • 1-<br> the<br> Nalt and Gil-<br> Cu2+<br> ad out- <br> what are the spectator ions in this reaction
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!