Balancing means there are equal amount of molecules on each side, both reactant and products. This is a method I like to do.
Under, I count how many molecules are in each side.
Cr2O3+Mg -->Cr + MgO
Cr: 2 1
O: 3 1
Mg: 1 1
Let's guess and make the number of oxygens equal on both sides.
Cr2O3+Mg -->Cr + 3MgO
Cr: 2 1
O: 3 3 EQUAL
Mg: 1 3
See what we did there? We multiplied the MgO on the products side by 3 so we can have 3 oxygens. Now let's multiply the Mg on the reactants by three so Mg AND O can be equal.
Cr2O3+3Mg -->Cr + 3 MgO
Cr: 2 1
O: 3 3 EQUAL
Mg: 3 3 EQUAL
Finally, we just need to multiply the loner Cr in the products side by two to make it equal for all elements.
Cr2O3+3Mg -->2Cr + 3 MgO
Answer:
Double bond
Explanation:
Carbon is a tetravalent atom. This implies that the carbon atom always forms four covalent bonds.
These four covalent bonds may be single, double or triple bonds. Compounds that contain double and triple bonds are said to be "unsaturated".
If the last carbon atom of an unsaturated fatty acid is bonded to two hydrogen atoms and one carbon atom, it means that the bond between the last carbon and the other carbon atom must be a double bond because carbon must be tetravalent and we have already been told that the fatty acid is unsaturated.
The last carbon atom of the unsaturated fatty acid must form two covalent bonds to the other carbon atom in order to respect the tetravalency of carbon.
A solution's pH will be a number between 0 and 14. A solution with a pH of 7 is classified as neutral. If the pH is lower than 7, the solution is acidic. When pH is higher than 7, the solution is basic. These numbers describe the concentration of hydrogen ions in the solution and increase on a negative logarithmic scale. For example, If Solution A has a pH of 3 and Solution B has a pH of 1, then Solution B has 100 times as many hydrogen ions than A and is therefore 100 times more acidic.
Uses of isotopes:
In agriculture,
C-14 is used to trace the path of photosynthesis.
In medicine,
Iodine -131 is used in the treatment of
goiter
Answer:
The only PH range which is not covered by any of the given components of the universal indicator is 7.6-8.0
Hence the PH range 7.6-8 can't be described using universal indicator.