Answer:
a) formula for citric acid is - C6 H8 o7
b) lime water turns opaque after adding co2 due to the formation of calcium carbonate.
c) reaction 3 is displacement reaction where a high reactive metal displace a less reactive from its salt solution.
d) reaction 1) is combination reaction where two reactant combines to give a single product whereas reaction 2) is decomposition reaction where a single reactant splits into more that 1 products.
Answer: a)
: Decomposition
b)
: double displacement
c)
: Synthesis (Combination)
d)
: redox
Explanation:
Decomposition is a type of chemical reaction in which one reactant gives two or more than two products.

A double displacement reaction is one in which exchange of ions take place.

Synthesis reaction is a chemical reaction in which two reactants are combining to form one product.

Redox reaction is a type of chemical reaction in which oxidation and reduction takes place in one single reaction. The oxidation number of one element increases and the oxidation number of other element decreases.

Answer:
10-10 above the 0 is positive and the ones below is - (negitive)
Explanation:
There are several differences between a physical and chemical change in matter or substances. A physical change in a substance doesn't change what the substance is. In a chemical change where there is a chemical reaction, a new substance is formed and energy is either given off or absorbed.