The melting point of NaCl is very high, 801°C. It is reduced to 600°C by the addition of _ in Down's process.
Correct answer: A. Calcium chloride
- A. Calcium chloride
- B. Magnesium chloride
- C. Aluminium chloride
- D. Potassium chloride
Explanation
Sodium chloride melts at a very high temperature. A mixture containing(NaCl+CaCl2) is used to decrease the melting point. The main reasons for lowering the temperature are:a) Sodium is volatile at this temperature and so a part of the metal formed may vaporize.b) At this high temperature, sodium and chlorine produced corrode the vessel.Calcium chloride, CaCl2, is added to lower the melting point of the cell medium from the normal melting point of NaCl, 804oC, to around 600oC.
Last updated
About Biological Molecules
The chapter covers water's polarity and biological roles, carbohydrates, lipids, proteins and nucleic acids, including their monomers, bonds, structures and functions. It also distinguishes RNA from DNA and explains conjugated molecules such as glycoproteins, glycolipids and nucleoproteins, which combine organic molecules with a non-protein component.
Practise Biological Molecules
1,790 free Biological Molecules MCQs from Biology, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Exams that ask Biology questions like this
Biology is on 6 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
Related questions
A common carbohydrate composed of glucose and fructose joined by a linkage between C-1 of glucose and C-2 of fructose is:
A complex aminoacid subunits is called?
A compound produced as a result of a chemical reaction of an alcohol with an acid, where a water molecule is released, is called:
A compound produced as a result of a chemical reaction of an alcohol with an acid in which water molecule is released is called_.
A dipeptide glycylalanine consists of: