Answer:
Physical and chemical changes are different because one deals with changes to ones shape or form, while chemical is changing one substance to another.
Explanation:
A example of a physical change would be cutting a block of wood into a cube of would, its physical change changes from a block to a cube. A chemical change is changing the substance into another substance so for example, burning that cube of wood in a fire. The fire is burning the wood into ash meaning it's no longer wood but ash.
Hope this helps.
Answer:
- <em><u>A physical change has occurred, with no energy change.</u></em>
Explanation:
When a pencil lead is broken there is not change of any chemical properties, therefore it is not a chemical change, but just a physical change. In this case the change is just the number of pieces and dimensions.
Chemical changes always involve the formation of new different substances; the bonds between the atoms of the starting substances (reactants) breake and new bonds are formed leading to new substances (products) with different chemical composition (arrange of atoms). Chemical changes occur through chemical reactions.
Hence, if there is not change on the chemical composition, you think on physical changes. Physical changes include change in shape, size, state of matter (e.g. solid, liquid, gas). In the case of a pencil lead breaking, it is a change in shape and size.
Also, since energy has not been absorbed or released during the change, the energy of the pencil lead before having been broken is equal to the sum of the energies of the pieces of pencil lead obtained. So, this is a physical change with no energy changes.
Some examples of physical changes that include change in energy are the change of state (e.g. solid to liquid or liquid to gas) and the dissolution of a compound.
To determine if the compound is an ionic compound, heat it up until the compound reaches its melting point and become molten. Use the molten form to set up an electric circuit and see if the compound will conduct electricity. If the compound conduct electricity then it is an ionic compound. If it does not conduct electricity, it is not an ionic compound. Ionic compounds usually conduct electricity in their molten forms.<span />
Answer:
The C4+ ion has the smallest ionic radius
Explanation:
In the periodic table, the size of an atom increases on going downwards in a group.
On the other hand, in a period, size decreases on going from left to right
The size of cation is smaller than its parent atom.
Lithium-ion (Li+) is the most left so it has the biggest radius.
More to the right ( this means a smaller ionic radius) , we have Berylium-ion (Be2+).
More to the right, so smaller than Be2+, we have B3+
The ion the most to the right, we have C4+
The C4+ ion has the smallest ionic radius
Li+ > Be2+ > Be3+ > C4+
