hello all need aa little hel with math if possible..trying to make stannous chloride test solution i have a recipe for 500ml i only want to make 15 ml in a test bottle. the mix i hae is 8g stannous to 500ml hydrochloric what would i need to make 15ml at the rate i am going 500ml would last me a life time and it has no shelf life any help would be appreciated thanks bob