Advertisements
Advertisements
प्रश्न
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.
State which of the measurements you would accept, giving the reason.
Advertisements
उत्तर
The metre stick is graduated in millimetres i.e. 1 mm to 1000 mm, and 1 mm = 0.1 cm. Therefore, if length is measured in centimetres, the least count of metre stick is 0.1 cm. The results 12.6 cm has the least count of 0.1 cm and is acceptable result.
APPEARS IN
संबंधित प्रश्न
Explain the term Saturated solution giving examples.
Dinitrogen and dihydrogen react with each other to produce ammonia according to the following chemical equation:
\[\ce{N2 (g) + 3H2 (g) → 2NH3 (g)}\]
(i) Calculate the mass of ammonia produced if 2.00 × 103 g dinitrogen reacts with 1.00 × 103 g of dihydrogen.
(ii) Will any of the two reactants remain unreacted?
(iii) If yes, which one and what would be its mass?
Why does the molarity of a solution depend upon temperature?
Solve the following problem:
Find out the molar mass of the following compounds:
Mohr’s salt [FeSO4(NH4)2SO4.6H2O]
(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:
5.16 × 104
Solve the following problem:
Write the following number in ordinary decimal form:
0.011 × 10−3
Solve the following problem:
Perform the following calculation. Round off your answer to two digits.
`(1.4xx10^9)/((2.77xx10^3)(3.76xx10^5))`
Perform each of the following calculations. Round off your answers to three digits.
(3.26104) (1.54106)
Perform the following calculation. Round off your answer to three digits.
(8.39 107) (4.53 109)
Solve the following problem:
Perform the following calculation. Round off your answer to three digits.
`(8.94xx10^6)/(4.35xx10^4)`
Solve the following problem:
Perform the following calculation. Round off your answer to three digits.
`((9.28xx10^9)(9.9xx10^-7))/((511)(2.98xx10^-6))`
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?
When light is passed through water containing a few drops of milk, it shows a bluish tinge. This is due to the ______ of light by milk and the phenomenon is called ______. This indicates that milk is a ______ solution.
A child wanted to separate the mixture of dyes constituting a sample of ink. He marked a line by the ink on the filter paper and placed the filter paper in a glass containing water as shown in Fig.2.3. The filter paper was removed when the water moved near the top of the filter paper.
(i) What would you expect to see, if the ink contains three different coloured components?
(ii) Name the technique used by the child.
(iii) Suggest one more application of this technique.
Calculate the mass of sodium sulphate required to prepare its 20% (mass percent) solution in 100g of water?
What will be the molarity of a solution, which contains 5.85 g of NaCl(s) per 500 mL?
If the concentration of glucose \[\ce{(C6H12O6)}\] in blood is 0.9 g L–1, what will be the molarity of glucose in blood?
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) \[\ce{20 g of KOH in 200 mL of solution}\]
If 4 g of \[\ce{NaOH}\] dissolves in 36 g of \[\ce{H2O}\], calculate the mole fraction of each component in the solution. Also, determine the molarity of solution (specific gravity of solution is 1g mL–1).
With increase of temperature, which of these changes?
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 molality of solution containing 15.20 g of urea, (molar mass = 60) dissolved in 150 g or water is ______.
Find the molality of solution if boiling point increases by 1.75 K and molal elevation constant of solvent is 5K kg mol-1.
