What is the bond order of O 2 ?

Correct Answer: In a chemical reaction, substances (elements or compounds) called reactants are changed into other substances (compounds or elements) called products Hence, reactants are those which start the chemical reaction For example: 1 In the burning of natural gas, methane (CH4) and oxygen (O2) are the reactants in the chemical reaction are the substances formed by a chemical reaction In the burning of natural gas, carbon dioxide (CO2) and water (H2O) are the products formed by the reaction 2 H2+O2 ----> H2O Here H2 & O2 are called Reactants and H2O is called Product

Correct Answer: 149.08

Explanation:

The gram formula mass is nothing but molar mass.

 

Composition :

 

Symbol      Element       Atomic weight       Atoms
   

     P         Phosphorus       30.973762               1       = 30.973
   

     O         Oxygen             15.9994                  4       =  63.998
   

     N         Nitrogen            14.0067                  3       =  42.020
   

     H         Hydrogen          1.00794                  12      =  12.096

   

Total   =  30.973+63.998+42.020+12.096 = 149.087

Correct Answer: TRUE

Explanation:

The process of conversion of milk into curd is called fermentation.  It is a chemical change. Milk consists of globular proteins called casein. As the microorganism lactobacillus react with milk and turn it to curd. For it 37 degree temperature is needed. But sometimes when it does not get favourable condition, then other microorganism react and makes the curd taste different.

Correct Answer: nonpolar, with a symmetrical distribution of charge

Explanation:

CF4 is tetrahedral.

Since the four 'F' atoms have the same electronegativity values, there is no bias in electron distribution toward any one.

 

Therefore, electron/charge distribution is symmetrical, which also means that the molecule is nonpolar.

 

Hence, CF4 is nonpolar molecule with a symmetrical distribution of charge.

Correct Answer: CF4

Explanation:

You have to consider three things.

1. First, are the bonds polar?

Look at differences in electronegativity and if  it is >0.5, bonds are polar.

 

2. Second, does the molecule have unshared electron pairs?

If so, they generally lead to a polar molecule.

 

3. Third, is the molecule symmetric?

If so, then although the bonds may be polar, the symmetry cancels out the individual bond polarity and the molecule is non polar.

CF4 follows all the rules above and has a symmetric distribution of charge, making it nonpolar. The others all have asymmetric charge distributions.

 

Hence, CF4 represents a Non-polar molecule.

Correct Answer: Lose electrons and forms cations

Explanation:

When combining with nonmetallic atoms, metallic atoms generally will Lose electrons and forms cations.

 

As the ionization energy of te metals are very low, so they can easily lose electrons and form positively charged ion called cations.

Correct Answer: Sucrose

Explanation:

Sucrose is not a monosaccharide.

 

Monosaccharides are simple carbohydrates molecules that cannot be broken down into smaller molecules of other carbohydrates.

 

Glucose, galactose and fructose are examples of Monosaccharides.

Correct Answer: Lithium

Explanation:

Electronegativity is the tendency for an atom to attract electrons. There are general trends on the periodic table which you can use to determine the relative electronegativity for different elements, but otherwise you can also look at their valence shell and effective nuclear charge to determine their relative electronegativity.

 

Here from the given options, Lithium has least tendency to attract electrons and thus has a lower electronegativity.

Correct Answer: Oxygen

Explanation:

Rust forms when oxygen reacts with chemicals in rocks, and that is often the case with many other elements in general. Like a copper nail being exposed to the air will rust.

Correct Answer: Here I give you the first 30 Atomic elements names and their Atomic masses Atomic number Element Atomic mass 1 Hydrogen 1 2 Helium 4 3 Lithium 694 4 Beryllium 901 5 Boron 1081 6 Carbon 1201 7 Nitrogen 1401 8 Oxygen 1599 9 Fluorine 1900 10 Neon 2018 11 Sodium 2299 12 Magnesium 2531 13 Aluminium 2698 14 Silicon 2809 15 Phosphorus 3097 16 Sulphur 3207 17 Chlorine 3545 18 Argon 3995 19 Potassium 3910 20 Calcium 4008 21 Scandium 4496 22 Titanium 4787 23 Vanadium 5094 24 Chromium 24 52 25 Manganese 5494 26 Iron 5585 27 Cobalt 5893 28 Nickel 5869 29 Copper 6355 30 Zinc 6541