Which monosaccharide rarely occurs freely in nature but is tied up in milk

Which monosaccharide rarely occurs freely in nature but is tied up in milk sugar until it is freed during digestion?

2 months ago

Solution 1

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2 months ago




Milk sugar contains the disaccharide called lactose.

A disaccharide is formed from the condensation of two monosaccharides.

Lactose is formed from the condensation of glucose and galactose.

Galactose rarely occurs freely in nature. It is freed when the enzyme lactase breaks down lactose during digestion.

📚 Related Questions

Choose the pair of substances that are most likely to form a homogeneous solution.A) KI and HgB) LiCl and C6H14C) C3H8 and C2H5OHD) F2 and PF3E) NH3 and CH3OH
Solution 1

A homogenous solution is a solution that has similar or uniform  composition and the properties remain constant through the solution. As compared to the heterogeneous solution that is different solution.

  • Methanol and anomia have a similar solution that is NH3 and CH3OH. Both have a similar bonding as compared to the rest.

Hence the option E is correct.

Learn more about the pair of substances that are most likely to form a homogeneous.


Solution 2


The answer is NH3 and CH3OH


The basic rule of a reaction is "like dissolves like" and for a homogenous mixture to form, there must be some common properties related to bonding.

1. KI and Hg

Normally mercury tends to form amalgam which is not a homogeneous solution.

2. LICL and C6H14

One is non polar and other is polar which makes the homogeneous reaction not possible.

3. C3H8 and C2H5OH

Both are miscible but will not develop homogeneous solution as propane is gas at normal temperature.

4. F2 and PF3

Flourine is highly electronegative and will repel fellow flourine making it not possible for homogeneous solution

5. NH3 and CH3OH

Both have same type of bonding and can react homogeneously.  

Calculate the energy required to produce 7.00 mol Cl2O7 on the basis of the following balanced equation. 2Cl2(g) + 7O2(g) + 130 kcal --> 2Cl2O7(g) Select one: a. 7.00 kcal b. 65 kcal c. 130 kcal d. 455 kcal
Solution 1


As the given chemical reaction equation is as follows.

      2Cl_{2}(g) + 7O_{2}(g) + 130 kcal \rightarrow 2Cl_{2}O_{7}(g)

Also, it is given that for 2 moles the energy required is 130 kcal. This means that energy required for 1 mole is calculated as follows.

                   1 mole = \frac{130 kcal}{2}

                               = 65 kcal

Hence, energy required for 7 moles will be calculated as follows.

              Energy required = 7 \times 65 kcal

                                           = 455 kcal

Thus, we can conclude that energy required to produce 7.00 mol Cl_{2}O_{7} on the basis of given reaction is 455 kcal.

Which organ system has the principal function of protection, water retention, thermoregulation, vitamin D synthesis, cutaneous sensation and nonverbal communication?
Solution 1


Explanation: The Skin is the largest organ of the body,it is located on the outside of the human body,it carries out several activities aimed at ensuring the well-being of a organisms.

The following are some of the activities of the Skin

Osmoregulation ( regulation of the internal environment through osmosis), protection (prevents certain substance from entering the body),Water retention ( holds enough water required for moisturizing the body), thermoregulation (manages the internal temperature of the body),Vitamin D synthesis, cutaneous sensation and nonverbal communication etc.

How much positive charge is in 0.7 kg of lithium? with each atom having 3 protons and 3 electrons. The elemental charge is 1.602 × 10−19 C and Avogadro’s number is 6.023 × 1023 . Answer in units of C.
Solution 1


As a neutral lithium atom contains 3 protons and its elemental charge is given as 1.602 \times 10^{-19} C. Hence, we will calculate its number of moles as follows.

          Moles = \frac{mass}{\text{molar mass}}

                     = \frac{0.7 \times 1000 g}{7 g/mol}

                     = 100 mol

According to mole concept, there are 6.023 \times 10^{23} atoms present in 1 mole. So, in 100 mol we will calculate the number of atoms as follows.

        No. of atoms = 100 \times 6.023 \times 10^{23}

                               = 6.023 \times 10^{25} atoms

Since, it is given that charge on 1 atom is as follows.

                     3 \times 1.602 \times 10^{-19}C

                    = 4.806 \times 10^{-19}C

Therefore, charge present on 6.023 \times 10^{25} atoms will be calculated as follows.

    6.023 \times 10^{25} atoms \times 4.806 \times 10^{-19} C

            28.95 \times 10^{6}C

Thus, we can conclude that a positive charge of 28.95 \times 10^{6}C is in 0.7 kg of lithium.

Approximately what percentage of bound oxygen is released to the cells for metabolism during an erythrocyte’s journey through the circulatory system?
Solution 1




Oxygen taken in the lungs have to circulate to the tissues through the blood. The erythrocytes contains hemoglobin which has a heme part that binds to 4 molecules of Oxygen. As it begins to circulate around the body, the heme portion begins to release oxygen. And it releases approximately 25% as it circulates through the circulatory system

By which mechanism would a steroid molecule diffuse into the cell?
Solution 1

Answer: Directly through the phospholipid membrane


The cell membrane consist of a phospholipid bilayers structure. In the interior of the membrane, the phospholipid tail are hydrophobic, which makes the cell membrane to be selectively permeable, it is permeable to non polar molecules and impermeable to polar molecules.

Because Steroids are fat soluble, non polar compounds, they can diffuse directly through the hydrophobic, non polar core of the phospholipid bilayer without the use of carrier proteins.

Magnesium metal burns in oxygen gas to produce magnesium oxide. How many grams of magnesium oxide will be formed from 16.1 g of oxygen gas? 1. 20.3 g 2. 40.6 g 3. 81.1 g 4. 65.0 g
Solution 1




Firstly, we write a balanced chemical equation for the chemical reaction as follows:

2Mg + O2 —-> 2MgO

Theoretically, 2 moles of oxygen gas reacted with 1 mole of magnesium metal to give 2 moles of magnesium oxide.

We now look at what actually happened. From the question, 16.1g of oxygen gas reacted. We need to know the number of moles of oxygen gas in 16.1g of oxygen gas.

Mathematically, the number of moles equals mass divided by molar mass. The molar mass of the oxygen gas is (2 * 16) = 32g/mol. Hence, the number of moles of the oxygen gas reacted is 16.1/32 = 0.503125 moles

Now theoretically, we know that 1 mole of oxygen yielded 2 moles of magnesium oxide, this means 0.503125 mole of oxygen would have yielded 2 * 0.503125 mole of magnesium oxide which equals 1.00625 mole.

Now, we find the mass of magnesium oxide corresponding to this number of moles. We need to know the molar mass of magnesium oxide which is 40.3044g/mol. The mass is given by 1.00625 * 40.3044 = 40.556g

A 2.300×10−2 m solution of nacl in water is at 20.0∘c. the sample was created by dissolving a sample of nacl in water and then bringing the volume up to 1.000 l. it was determined that the volume of water needed to do this was 999.4 ml . the density of water at 20.0∘c is 0.9982 g/ml.
Solution 1

The given question is incomplete. The complete question is as follows.

A 2.300×10−2 m solution of nacl in water is at 20.0∘c. the sample was created by dissolving a sample of nacl in water and then bringing the volume up to 1.000 l. it was determined that the volume of water needed to do this was 999.4 ml . the density of water at 20.0∘c is 0.9982 g/ml.

Calculate the molality of the salt solution.

Express your answer to four significant figures and include the appropriate units.


Molality is defined as the number of moles present in kg of a solvent.

Mathematically,     Molality = \frac{\text{moles of solute}}{\text{mass of solvent}}


      Mole of solute = Molarity of solute x Volume of solution

                               = (0.0230 M) x (1.000 L) = 0.0230 mol of solute

Therefore, mass of solvent will be as follows.

     999.4 mL \times (\frac{0.9983 g}{1 mL})

                  = 997.7 g

                  = 0.9977 kg        (as 1 kg = 1000 g)

Therefore, we will calculate the molality as follows.

          Molality = \frac{0.0230 mol}{0.9977 kg}

                   = 0.02306 mol/kg

thus, we can conclude that molality of the given solution is 0.02306 mol/kg.

Must all four hydrogen atoms lie in the same plane? If not, what is the spatial relationship among them? Why?
Solution 1


We are considering an Allene molecule here, CH2CCH2. To answer your question, NO, they don't have to lie on the same plane. The spatial arrangement between them is that the center carbon that forms these pi bind in the left and right are PERPENDICULAR to each other.


We see here that The terminal carbons are sp2 hybridized, and form three σ-bonds each which means that each terminal carbon has one unhybridized p-orbital. The central carbon atom is sp hybridized, and forms two σ-bonds which means it has two unhybridized p-orbitals. For better understanding, let's call these two orbitals px and py. Summarily, These orbitals are perpendicular to each other

Which of the following statements regarding isotopes is TRUE? a. Isotopes have the same number of protons and neutrons, but vary in the number of electrons they contain. b. Isotopes of an element have the same atomic number, but have different atomic masses. c. The chemical properties of ALL of an element's isotopes are EXACTLY the same. d. The atomic weight of any element is approximately equal to the mass number of its most abundant isotope. e. B, C, and D. All of the statements are true regarding isotopes
Solution 1




A. Is wrong

Isotopes do not have same number of neutrons. They only contain the same number of protons and hence same number of electrons.

B is correct

Isotopes are the different atoms of a particular single element which have exactly the same number of protons but varying number of neutrons.

C is correct

The chemical properties are a function of the electrons since they are the ones involved in chemical bonding. Since the number of electrons are the same, it is expected that they have similar chemical properties.

d is correct

It is the weight of the most abundant isotope that clearly determines the weight of the atom. In fact, the weight of the atom is closest in value to the weight of the atom with the highest abundance

e is correct as all the options here are correct

D is wrong, not all options are correct