Answer:
Demonstration 1 showed a chemical change because a new gaseous substance was formed, and demonstration 2 showed a physical change because liquid water became water vapor.
Explanation:
Chemical changes alter the chemical makeup of a subject, and a physical change only alters the appearance of a subject, not the chemical makeup.
Answer:
1) False
2) there are equal amounts of rectants and products
Explanation:
1) When dynamic equilibrium is achieved. the rate of forward and backward reaction they are the same, that is to say, two opposite reactions occur at the same rate, keeping the concentrations constant over time. Different to say the rate of the ractions go to zero.
2) A chemical equilibium exists when what is produce in quantities is equal to what reacts.
So the correct answer is the literal (d).
Answer:
Answer to number one
Explanation:
Polyethylene terephthalate (PET) is a plastic material used for milk packaging.
Answer:
8
Explanation:
Oxidation:
Reduction:
We have to equalise the number of moles of electrons gained and lost in a redox reaction in order to get a balanced reaction.
Hence we have to multiply the oxidation reaction throughout by 6.
and adding the two half-reactions we obtain:
Still the total charge and number of oxygen is not balanced.
Since the reaction takes place in acidic conditions, we will add required number of H+ to the appropriate side to balance the charge and add half the amount of H2O to balance the hydrogen atoms.
We add 14 H+ on LHS and 7H2O on RHS to obtain:
Sum of coefficients of product cations = 6+2 = 8
