Think about the following changes and decide whether they are physical or chemical changes. Write the type of change and reasons for that in the table.(a) Twinkling of stars (b) Cooking of vegetables (c) Cutting of fruits (d) Rusting of iron(e) Combustion of magnesium ribbon (f) Burning of candle

classify the following processes into physical changes or chemical changes? (a) Twinkling of stars (b) Cooking of vegetables (c) Cutting of fruits (d) Boiling of waters. (e) Rusting of iron (f) Combustion of magnesium ribbon (g) Burning of candle (h) Melting of wax

Classify the changes involved in the following processes as Physical, Chemical or both. a) Burning of coal b) Melting of wax. c) Beating aluminium to make aluminium foil. d) Digestion of food. e) Boiling of egg. f) Photosynthesis. g) Cutting of wood

a) If we dip the iron nail in the solution of copper sulphate, what changes can you observed? b) Write the chemical equation. c) What type of reaction it is?

According to molecular orbital theory, atomic orbitals of nearly same energy of different atoms are combined and form molecule. In homodiatomic molecule two atomic orbitals which have wave function psi_(A) and psi_(B) are combined in two ways (psi_(A)pm psi_(B)) . They have two type of electron density, one is bonding [(psi_(A) pm psi_(B))^(2)] where e- density increase between nucleus. Another is antibonding [(psi_(A)pm psi_(B))^(2)] where e^(-) density decreases between nucleus. These molecular orbitals are filled according to Hund, Pauli, afbau principle. Existence of molecule depends on bond order. where bond order = ("Number of bonding "e^(-)"s- number of antibonding "e^(-)s)/(2) lf the molecule have unpaired electron it is paramagnetic otherwise diamagnetic Statement- 1: Removal of two e^(-) from N^(2) , magnetic behaviour does not change while addition of two electrons in O_(2) magnetic behaviour changes. Which of the following correct trends of bond energy is possible to explain by following statement. "Successive filling of antibonding orbital reduce the bond energy between two atoms"? (I ) N_(2) gtgt O_(2) gtgtF_(2) (II) O_(2)^(+) gt O_(2) gt O_(2)^(-) (III) C_(2)^(2) gt C_(2) (IV) CI_(2) gt Br_(2) gt F_(2)

Identify the type of energy change (ionization energy, energy of atomization, etc) show by each of these steps in the Born Haber cycle for potassium chloride. State with a reason whether the step is exothermic or endothermic. a ) 1//2 CI_(2)(g) rarr CI(g) " " b) CI(g) rarr CI^(-)(g) " " c) K(s) rarr K (g) d) K(g) rarr K^(+) (g) + e^(-) " " e) K (s) +1//2 CI_(2) (g) rarr KCI (s) " " f) KCI (s) rarr K^(+) (g) + CI^(-) (g)

Angle batween velocity and acceleration vectors in the following case {:("List-I", "List-II"),((A)"Vertically projected body",(e)90^(@)),((b) "For freely falling body",(f)"Changes from point to point"),((C)"For projectile",(g)"Zero"),((d)"In uniform circular motion",(h)180^(@)):}