Advertisements
Advertisements
प्रश्न
Solve the following problem:
Perform the following calculation. Round off your answer to two digits.
`1/(3.40xx10^24)`
उत्तर
`1/(3.40xx10^24)`
= 0.2941 × 10–24
= 2.941 × 10–25
= 2.9 × 10–25
APPEARS IN
संबंधित प्रश्न
Explain the term Saturated solution giving examples.
A sample of drinking water was found to be severely contaminated with chloroform, CHCl3, supposed to be carcinogenic in nature. The level of contamination was 15 ppm (by mass).
- Express this in percent by mass.
- Determine the molality of chloroform in the water sample.
Calculate the molarity of a solution of ethanol in water in which the mole fraction of ethanol is 0.040 (assume the density of water to be one).
Explain the term mole fraction
Explain the term molality
Solve the following problem:
Find out the molar mass of the following compounds:
Copper sulphate crystal (CuSO4.5H2O)
(At. mass: Cu = 63.5; S = 32; O = 16; H = 1; Na = 23; C = 12; Fe = 56; N = 14)
Solve the following problem:
Find out the molar mass of the following compounds:
Sodium carbonate, decahydrate (Na2CO3.10H2O)
(At. mass: Cu = 63.5; S = 32; O = 16; H = 1; Na = 23; C = 12; Fe = 56; N = 14)
Solve the following problem:
Write the following number in ordinary decimal form:
3.49 × 10−11
Solve the following problem:
Write the following number in ordinary decimal form:
3.75 × 10−1
Solve the following problem:
Write the following number in ordinary decimal form:
43.71 × 10−4
Solve the following problem:
Write the following number in ordinary decimal form:
14.3 × 10−2
Solve the following problem:
Perform the following calculation. Round off your answer to two digits.
`(1.4xx10^9)/((2.77xx10^3)(3.76xx10^5))`
Solve the following problem:
Perform the following calculation. Round off your answer to two digits.
`((4xx10^-3)(9.9xx10^-7))/((789)(1.002xx10^-10)(0.3xx10^2))`
Perform each of the following calculations. Round off your answers to three digits.
(3.26104) (1.54106)
Solve the following problem:
Your laboratory partner was given the task of measuring the length of a box (approx 5 in) as accurately as possible, using a metre stick graduated in milimeters. He supplied you with the following measurements:
12.65 cm, 12.6 cm, 12.65 cm, 12.655 cm, 126.55 mm, 12 cm.
Give your reason for rejecting each of the others.
Solve the following problem:
The hourly energy requirements of an astronaut can be satisfied by the energy released when 34 grams of sucrose are “burnt” in his body. How many grams of oxygen would be needed to be carried in space capsule to meet his requirement for one day?
Non-metals are usually poor conductors of heat and electricity. They are non-lustrous, non-sonorous, non-malleable and are coloured.
Name a lustrous non-metal.
If 500 mL of a 5 M solution is diluted to 1500 mL, what will be the molarity of the solution obtained?
Which of the following solutions have the same concentration?
(i) \[\ce{20 g of NaOH in 200 mL of solution}\]
(ii) \[\ce{0.5 mol of KCl in 200 mL of solution}\]
(iii) \[\ce{40 g of NaOH in 100 mL of solution}\]
(iv) \[\ce{20 g of KOH in 200 mL of solution}\]
Match the following physical quantities with units
| Physical quantity | Unit |
| (i) Molarity | (a) g mL–1 |
| (ii) Mole fraction | (b) mol |
| (iii) Mole | (c) Pascal |
| (iv) Molality | (d) Unitless |
| (v) Pressure | (e) mol L–1 |
| (vi) Luminous intensity | (f) Candela |
| (vii) Density | (g) mol kg–1 |
| (viii) Mass | (h) Nm–1 |
| (i) kg |
The molarity of pure water is ______.
With increase of temperature, which of these changes?
What quantity (in mL) of a 45% acid solution of a monoprotic strong acid must be mixed with a 20% solution of the same acid to produce 800 mL of a 29.875% acid solution?
250 g solution of D-glucose in water contains 10.8% of carbon by weight. The molality of the solution is nearest to ______.
(Given: Atomic weights are H, 1u; C, 12u; O, 16u)
The molarity of urea (molar mass 60 g mol−1) solution by dissolving 15 g of urea in 500 cm3 of water is ______.
Molarity is ______.
