Is Zakat obligatory on money deposited in an Islamic bank and designated for study and marriage? What is the value of Zakat, and can it be paid in installments from the quarterly profits?

If money reaches the nisab (the equivalent of 85 grams of gold) and a year has passed over it, zakat becomes obligatory on both the principal and the profit. 2.5% of the capital and profits should be given annually, and it is not permissible to delay it to pay it in installments. As for paying zakat in advance before the year is complete, it is permissible, and in this case, it is permissible to pay it in installments.