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प्रश्न
If the relative molecular mass of A is 90, what is the molecular formula of A?
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उत्तर
The relative molecular mass of A is 90
Empirical Formula mass of compound is = 45
Then, n = Molecular mass/ Empirical Formula Mass
= 90/45 = 2
Molecular formula of compound = n x Empirical formula
= 2 x (CO2H) = C2O4H2.
संबंधित प्रश्न
Give balanced chemical equations for the following conversions A, B, and C:
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2 X V.D. = Molecular mass.
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2KNO3 → 2KNO2 + O2
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(K = 39, 0 = 16, N = 14)
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[Fe = 56, S = 32, O =16, H = 1].
Chlorine, nitrogen, ammonia and sulphur dioxide gases are collected under the same conditions of temperature and pressure.
Copy the following table which gives the volumes of the gases collected, and the number of molecules (X) in 20L of nitrogen.You are to complete the table by giving the number of molecules in th e other gases, in terms of X.
| Gas | Volume(litres) | Number of molecules |
| Chlorine | 10 | |
| Nitrogen | 20 | X |
| Ammonia | 20 | |
| Sulphur dioxide | 5 |
Mention the term defined by the following sentence:
The mass of a given volume of gas compared to the mass of an equal volume of hydrogen.
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If 15.8g of potassium permanganate (VII) was used in the reaction, calculate the mass of iron (II) sulphate used in the above reaction.
A compound 'X' consists of 4.8% of C and 95.2% of Br by mass.
Name the type of chemical reaction by which X can be prepared from ethane.
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When heated, potassium permanganate decomposes according to the following equation :
\[\ce{2KMnO4 -> \underset{\text{solid residue}}{K2MnO4 + MnO2} + O2}\]
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