If a parcel of land is considered community property and the husband dies with a will leaving 50% to his wife and 25% to each of his two children, is he conveying in his will 50% of his 50% to his wife and 25% of his 50% to the children? Or just stating the obvious that she already has 50% via community property? And actually leaving his 50% to his two children?

Thanks in advance

Yes, his will can only address his 50%. So half od his half goes to wife and the other half of his half is split between his children. With no will eife would get all of his half