Question

please answer this as fast as possible​

Answer 1

Answer:

Px + 40 = Qx + 20

Px +20 = Qx

20 = Qx - Px = (Q-P)x

If Q=P then (Q-P)x = 0 for all x and thus the original equation has no solutions.

Explanation:

Answer 2

Answer:

4(a) The green crystals are the crystals of ferrous sulphate. (FeSO4. 7H2O)

Equation :- look at the photo.

4(b) slaked lime

4(c) limestone because the thin layer which Is formed after 2, 3 days of painting is due to reaction of CO2 with Ca(OH)2 which formes CaCO3 and water. And limestone is one of the forms of carbon carbonate.

4(d) Exothermic reaction

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