Chemistry
2019 · Paper 1
Take it one question at a time. Try an answer, then check your understanding.
Complete GATE CY 2019 Paper 1 overview, original pages and practice · Timed previous-paper practice
Questions 28–30 of 65. Imported answers require review unless explicitly marked reviewed.
Question 18
Open questionCYNAT1 markNeeds review
On heating a sample of 25 mg hydrated compound (molecular weight = 250 g/mol) in thermogravimetric analysis, 16 mg of dehydrated compound remains. The number of water molecules lost per molecule of hydrated compound is ____________.
(Molecular weight of water = 18 g/mol)
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Open questionCYNAT1 markNeeds review
The total number of α and β particles emitted in the following radioactive decay is ________.
²³⁸₉₂U → ²¹⁰₈₂Pb
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Open questionCYNAT1 markNeeds review
An ideal gas occupies an unknown volume V liters (L) at a pressure of 12 atm. The gas is expanded isothermally against a constant external pressure of 2 atm so that its final volume becomes 3 L. The work involved for this expansion process is ________ cal. (Round off to two decimal places)
(Gas constant R = 0.082 L atm mol⁻¹ K⁻¹ = 2 cal mol⁻¹ K⁻¹)
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