Physics, Chemistry, Mathematics Forums

Between 2 numbers whose sum is 13/6 an even number of arithmetic means is inserted.The sum of these means, exceeds their number by unity. How many means are there?

At 100degreeC and 1 atm, if the density of liquid water is 1.0g/cm^3 and that of water vapour is 0.0006g/cm^3, then the volume occupied by water molecules in 1L of steam at that temperature is

a 6cm^3

b 60cm^3

c 0.6cm^3

d 0.06cm^3

A staircase contains three steps each 10 cm high and 20 cm wide. What should be the minimum horizontal velocity of a ball rolling of the uppermost plane so that it hits directly the lowermost plane.

Maths Determinants Problem

Maths Matrix Problem

Maths Determinants Problem

What are hadrons?

how can we know that the given reaction is reversible or not?

for ex:-

Q.Which of the following is reversible reaction?

(A) Pb(NO3)2(aq) + 2NaI(aq) = PbI2(s) + 2NaNO3(aq)

(B) AgNO3(aq) + HCl(aq) = AgCl(s) + HNO3(aq)

(C)2Na(s) + 2H2O(l) = 2NaOH + H2(g)

(D) KNO3(aq) + NaCl(aq) = KCl(aq) + NaNO3(aq)

If, in ΔABC, (b+c)/11 = (c+a)/12 = (a+b)/13

prove that

(cosA)/7 = (cosB)/19 = (cosC)/25

Chemical properties of atoms are controlled by the no. of electrons, which are determined by no. of protons in a nucleus. Number of neutrons present in the nucleus have a very little effect on chemical properties of an element. Why?