JEE Main · 2024 · 05 Apr 2024 · Shift 1 · d and f Block Elements

WhatsApp Email

In a borax bead test under hot condition, a metal salt (one from the given) is heated at point B of the flame, resulted in green colour salt bead. The spin-only magnetic moment value of the salt is
____ BM (Nearest integer)
[Given atomic number of

Cu = 29, Ni = 28

Mn = 25, Fe = 26]

Answer: 6

Solution

A green bead in the borax bead test (heated in the outer/hot flame) is characteristic of iron as

F e^{3 +}

F e^{3 +}

3 d^{5}

with 5 unpaired electrons:

μ = n (n + 2) = 5 \times 7 = 35 = 5.92 BM \approx 6 BM .

Nearest integer

= 6

JEE Main · 2024 · 05 Apr 2024 · Shift 1 · Integer answer

Practise more: all JEE Main PYQs on d and f Block Elements →

More JEE Main questions on d and f Block Elements

$MnO_{4}^{2 -}$ , in acidic medium, disproportionates to :
JEE Main 2026View solution →
Consider the following reactions:
$NaCl + K_{2} Cr_{2} O_{7} + H_{2} SO_{4} \to A + KHSO_{4} + NaHSO_{4} + H_{2} O$ …
JEE Main 2026View solution →
Given below are some of the statements about Mn and $Mn_{2} O_{7}$ . Identify the correct statements
A. Mn forms the oxide $Mn_{2} O_{7}$ in which Mn is in its highest oxidation state.
B. Oxygen stabilizes the Mn in higher oxidation states by fo …
JEE Main 2026View solution →
On heating a mixture of common salt and $K_{2} Cr_{2} O_{7}$ in equal amount along with concentrated $H_{2} SO_{4}$ in a test tube, a gas is evolved. Formula of the gas evolved and oxidation state of the central metal atom in the gas r …
JEE Main 2026View solution →
Among the following oxides of 3d elements, the number of mixed oxides are _____. …
JEE Main 2026View solution →
The oxidation state of chromium in the final product formed in the reaction between KI and acidified $K_{2} Cr_{2} O_{7}$ solution is:
JEE Main 2026View solution →