प्रकाश परावर्तन तथा अपवर्तन -L4| Prakash Paravartan Tatha Apvartan|गोलीय दर्पण |Vigyan Class 10 Ch 1

प्रकाश का परावर्तन |परावर्तन के नियम |बिंब और प्रतिबिंब |समतल दर्पण से परावर्तन |गोलीय दर्पण |अपवर्तन |OMR

A home owner uses 4 . 00 xx 10^(3) m^(3) of methane (CH_(4)) gas, (assume CH_(4) is an ideal gas ) in a year to heat his home. Under the pressure of 1.0 atm and 300 K , mass of gas used is x xx 10^(5) g . The value of x is ______ (Nearest i nteger) (Given R = 0 . 083 L atm K^(-) mol ^(-) )

A buffer solution was made by adding 15.0 g of CH_(3) COOH and 20.5gCH_(3)COONa . The buffer is diluted to 1.0L . a. Calculate the pH of solution. b. What will be the change in pH if 10.0mL of 1.0 M HC1 is added to it. Given: pK_(a) of CH_(3)COOH = 4.74, log ((13)/(12)) = 0.035

A natural gas may be assumed to be a mixture fo methane and ethane only. On complete combustion of 10L of gas at STP the heat evolved was 474.6 kJ . Assuming Delta_(comb) H^(Theta) CH_(4)(g) =- 894 kJ mol^(-1) and composition of the mixture by volume.

0.5 L of 0.5 M CH_(3)COOH and 0.5 L of 0.25 M CH_(3)COONa are available. What maximum volume of a buffer with a pH =4.58 can be prepared using only these two resources ? K_(a) =1.8xx10^(-5)