answer.
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
o-na [289]
2 years ago
4

What is the molality of a d-mannose solution prepared by dissolving 45.0 g of d-mannose, c6h12o6, in 125.9 g of water?

Chemistry
1 answer:
Gennadij [26K]2 years ago
8 0
Molality is a unit of concentration that represents the moles of solute per kilogram of solvent. The solvent here is water.

Mass of solvent in kg = 125.9 g * 1 kg/1000 g = 0.1259 kg

The moles of d-mannose knowing that its molar mass is 180.156 g/mol,

Moles solute = 45 g * 1 mol/180.156 g = 0.2498 mol

Thus,
Molality = 0.2498/0.1259 = <em>1.98 m</em>
You might be interested in
Which letter indicates a subatomic particle with a mass of 5.489 x 10-4 amu
Ludmilka [50]

Answer:

electron

Explanation:

The electron is subatomic particle that revolve around outside the nucleus and has negligible mass. It has a negative charge.

Symbol = e⁻

Mass = 9.10938356×10⁻³¹ Kg

Mass in amu = 1/1838 = 5.4 × 10⁻⁴amu

It was discovered by j. j. Thomson in 1897 during the study of cathode ray properties.

While neutron and proton are present inside the nucleus. Proton has positive charge while neutron is electrically neutral. Proton is discovered by Rutherford while neutron is discovered by James Chadwick in 1932.

Symbol of proton= P⁺

Symbol of neutron= n⁰  

Mass of proton=1.672623×10⁻²⁷ Kg

Mass of neutron=1.674929×10⁻²⁷Kg

An atom consist of electron, protons and neutrons. Protons and neutrons are present with in nucleus while the electrons are present out side the nucleus.

All these three subatomic particles construct an atom

4 0
2 years ago
Read 2 more answers
Avanti works in a bookstore. She has four books and is going to place them in two stacks. The diagram above shows the books befo
Feliz [49]

Answer:

Well they didn't transfer any energy when they weren’t touching and it did t produce any energy if it didn’t move. Since they are on top of each other they are causing momentum on each other creating kinetic energy

Explanation:

3 0
1 year ago
Calculate the percent activity of the radioactive isotope strontium-89 remaining after 5 half-lives.
maria [59]
The answer to this question would be: 3.125%

Half-life is the time needed for a radioactive molecule to decay half of its mass. In this case, the strontium-89 is already gone past 5 half lives. Then, the percentage of the mass left after 5 half-lives should be:
100%*(1/2^5)= 100%/32=3..125%
5 0
2 years ago
Which runner has greater kinetic energy: a 46-kilogram runner moving at a speed of 8 meters per second or a 92-kilogram runner m
Lena [83]
Runner a has a greater kinetic energy
8 0
2 years ago
How many acidic protons are there in 0.6137 g of KHP?
andreyandreev [35.5K]

0.6137 g of KHP contains 1.086 × 10^21 acidic protons.

Number of moles of KHP = mass of KHP/molar mass of KHP

Molar mass of KHP = 204.22 g/mol

Mass of KHP = 0.6137 g

Number of moles of KHP = 0.6137 g/204.22 g/mol = 0.003 moles of KHP

Now,  1 each molecule of KHP contains 1 acidic proton.

For 0.003 moles of KHP there are; 0.003 × 1 × NA

Where NA is Avogadro's number.

So;  0.003 moles of KHP contains 0.003 × 1 × 6.02 × 10^23

= 1.086 × 10^21 acidic protons.

Learn more: brainly.com/question/16672114

7 0
2 years ago
Other questions:
  • After learning about climate change in her science class, Selena wants to make a few changes at home so she can affect climate c
    14·2 answers
  • The highest elevation Mt. Zembat in Alaska 40 years ago was measured at 7600 feet. Today the highest elevation is 7598 feet. Wha
    11·1 answer
  • Magnesium has an atomic mass of 24.3. there are two isotopes of magnesium - one contains 12 neutrons and the other contains 13 n
    7·1 answer
  • The half life of a certain radioactive element is 1,250 years what percent of the atoms remain after 7500 years
    8·2 answers
  • What is the volume of 43.7 g of helium at stp?
    15·2 answers
  • Question 2 Here are four sketches of pure substances. Each sketch is drawn as if a sample of the substance were under a microsco
    5·1 answer
  • The bond enthalpy of the C―N bond in the amide group of proteins can be treated as an average of C―N (276 kJ/mol) and C═N (615 k
    14·1 answer
  • Can 1750 mL of water dissolve 4.6 moles of Copper Sulfate CuSO4? _________ Why? / Why not?
    8·1 answer
  • Describe the valence electrons in nitrogen and how it could bond to other atoms.
    14·1 answer
  • When aqueous solutions of AgNO3 and KI are mixed, AgI precipitates. The balanced net ionic equation is ________. When aqueous so
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!