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Dry tests: heating, flame and borax bead tests

36 questions on Dry tests: heating, flame and borax bead tests from the Qualitative Analysis: Anions chapter: 8 NEET level, 16 JEE Main, 12 JEE Advanced. Each one opens with its answer and solution.

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In a flame test, a salt of which cation imparts an apple-green colour to the flame? NEET level
A borax bead containing a trace of a metal salt is green while hot and blue on cooling in the oxidising flame. In the reducing flame it becomes red and opaque. ... NEET level
A colourless crystalline salt is heated strongly in a dry tube. Brown fumes are evolved and a residue that is yellow on cooling remains. The salt is NEET level
A cobalt blue glass is often used while viewing the flame test of a potassium salt contaminated with sodium. Its purpose is to NEET level
A white solid gives off a gas that turns lime water milky when strongly heated. The residue is yellow while hot and becomes white on cooling. The solid is most ... JEE Main level
Assertion: The borax bead test is useful only for salts of some d-block metals, because colourless metals give colourless beads. Reason: On heating, borax gives... JEE Main level
Which of the following pairs of cation and flame colour are correct? JEE Main level
Match the salt in List I with the observation on strong heating in List II. List I: (P) CuCO3 (Q) ZnCO3 (R) (NH4)2Cr2O7 (S) Pb(NO3)2 List II: (1) swollen green ... JEE Main level
A borax bead made with a trace of a salt is yellow-brown when hot and yellow when cold in the oxidising flame, and bottle green in the reducing flame. The metal... JEE Main level
A 1.68 g sample of a white solid is heated strongly. A gas that turns lime water milky is evolved, and water droplets condense on the cool part of the tube. Ato... JEE Main level
Which of the following ammonium salts leaves a non-volatile residue when heated strongly in a dry hard-glass tube? JEE Main level
Which of the following statements about the borax bead test are correct? JEE Advanced level
A salt X on strong heating gives brown fumes, and a black residue which dissolves in dilute H2SO4 to give a blue solution. The original salt gives a blue-green ... JEE Advanced level
Ammonium dichromate is heated and the swollen green residue is then fused in a borax bead. The number of electrons transferred per formula unit of the salt in i... JEE Advanced level
A white solid Y dissolves in water to give an alkaline solution and imparts a persistent golden-yellow flame. It swells on heating and fuses to a glassy mass. W... JEE Advanced level
Which of the following statements about the action of heat on nitrates are correct? JEE Advanced level
Green crystals Z lose water on gentle heating to give a white solid, which on strong heating leaves a red-brown residue and evolves a gas mixture. The gases are... JEE Advanced level
Which of the following statements on flame tests are correct? JEE Advanced level
A white solid X is heated strongly in a dry test tube. It evolves a colourless, odourless gas that turns lime water milky, and the residue is yellow while hot b... NEET level
Which cation imparts a crimson-red colour to the Bunsen flame? NEET level
On dry heating of the solid, which nitrate gives brown fumes of NO2 together with a metal oxide residue? NEET level
A borax bead is made with a trace of a copper(II) salt and heated in the oxidising (outer) flame. The colour of the bead after it has cooled is: NEET level
Green crystals of FeSO4.7H2O are heated strongly in a dry tube until no further change occurs. The gaseous products of the final decomposition of the anhydrous ... JEE Main level
Assertion: A borax bead containing a manganese salt is violet (amethyst) in the oxidising flame. Reason: In the bead manganese is present as manganese(II) metab... JEE Main level
Exactly one of the following solids gives a colourless, inert gas (not supporting combustion) together with a green solid residue on heating. It is: JEE Main level
Anhydrous copper(II) nitrate is heated until only a black solid remains. Assume every product other than the black solid is a gas. The moles of gaseous products... JEE Main level
A borax bead tinted with an unknown metal salt is yellow (cold) in the oxidising flame and bottle-green in the reducing flame. The metal is: JEE Main level
Match the cation (List I) with the flame colour (List II). List I: P Na+, Q K+ (through blue glass), R Ca^2+, S Ba^2+. List II: 1 apple-green, 2 brick-red, 3 li... JEE Main level
Select all correct statements about the flame tests. JEE Main level
Among the following solid carbonates, select all that decompose with evolution of CO2 on strong heating in a Bunsen flame (take the alkali metal carbonates Na2C... JEE Main level
Select all correct statements about borax bead tests (colours stated for the cold bead). JEE Main level
A white deliquescent solid X is soluble in water. When heated in a dry tube it evolves a brown gas and a colourless gas that rekindles a glowing splinter, and t... JEE Advanced level
A white crystalline solid X crackles (decrepitates) on heating, evolving a brown gas and a colourless gas that rekindles a glowing splinter. The residue is yell... JEE Advanced level
Blue crystals of CuSO4.5H2O are heated first gently and then to a bright red heat. Select all correct statements. JEE Advanced level
A borax bead dipped in a manganese(II) salt becomes violet on cooling after heating in the oxidising flame; the colour is due to manganese(III) metaborate. Taki... JEE Advanced level
A white solid X imparts a brick-red colour to the flame. On strong heating up to about 1000 degC it first gives a gas that burns with a blue flame, leaving a re... JEE Advanced level