ডিস্ট্রিবিউটিভ প্রোপার্টি ব্যবহার করে নিচের প্রতিটির গুণফল খুঁজুন। 6754 xx 94 | 6 | পু...

The minimum energy required for the emission of photoelectron from the surface fo a metal is 4. 94 xx 10 ^(19) J . Calcualte the critical reequency and the corresponding wavelength of the critical frequency and the corresponding wavelngth of the photon requred to ejerct the electron. ( h = 6. 6 xx 10^(-234) J esc^(-1)) .

The planet Mars has two moons. Phobos and Delmos (i) phobos has period 7 hours, 39 minutes and an orbital radius of 9.4 xx 10^(3) km . Calculate the mass of Mars. (ii) Assume that Earth and mars move in a circular orbit around the sun, with the martian orbit being 1.52 times the orbital radius of the Earth. What is the length of the martian year in days? (G = 6.67 xx 10^(-11) Nm^(2) kg^(-2))

The sum of IE_(1) and IE_(2) and those of IE_(2) and those of IE_(3) and IE_(4) in (kJ mol^(-1)) of Ni and Pt are : {:(,(IE_(1)+IE_(2)),(IE_(2)+IE_(4)),"Total",),(Ni,2.5 xx 10^(3),8.8 xx 10^(3),11.3 xx 10^(3),),(Pt,2.7 xx 10^(3),6.7 xx 10^(3),9.4 xx 10^(3),):} a. What is the most common oxidation state (O.S.) of Ni and Pt . b. Name of the metal ( Ni or Pt ) which can more easily form compounds in its +4 O.S.

(a) 2 Calculate the number of moles of water in 366 g BaCl_(2).2H_(2)O . (b) Calculate the value of X ( in terms of mole) if X=9.4 g "Phenol" +6.02xx10^(22) molecules phenol +0.2 "mole" phenol.

(a) What is meant by saying that the potential difference two points is 1 volt ? Name a device that helps to measure the potential difference across a conductor. (b) Why does the connecting cord of an electric heater not glow hot while the heating element does ? ( c) Electrical resistivities of some substances at 20^@ C are given below : Silver 1.60 xx 10^-8 Omega m Copper 1.62 xx 10^-8 Omega m Tungsten 5.20 xx 10^-8 Omega m Iron 10.0 xx 10^-8 Omega m Mercury 94.0 xx 10^-8 Omega m Nichrome 100 xx 10^-6 Omega m . Answer the following question in relation to them : (i) Among silver and copper, which one is a better conductor ? Why ? (ii) Which material would you advise to be used in electrical heating devices ? Why ?

Density of Li is 0.53"g cm"^(-3) . The edge length of Li is 3.5Å . Find the number of Li atoms in a unit cell (N_(0)=06.023xx10^(23),M=6.94) .

Find the value of each of the following by using suitable properties : 785xx94+785xx6