If the value of Avogadro number is 6.023 × 1023 mol-1 and the value of Boltzmann constant is 1.380 × 10-23 JK-1, then the number of significant digits in the calculated value of the universal gas constant is _________.

k= NA​R​R = k / NA​= 1.380×10−23 × 6.023 x 1023= 8.31174In these operations, the result must be reported with least number of significant figures .. Hence, the answer is 8.312,So, number of significant number in 8.312 is 4.