JSFiddle - React, Tailwind, and code Playground

JavaScript

var arr = ['topic1',497,'topic2',591,'topic3',17,'topic4',980];
var objectArray = [];

for(let i = 0; i < arr.length - 1; i+=2){
    objectArray.push({"topic": arr[i], "count": arr[i+1]})
}
console.log(objectArray);