Question

What is the formula of white ppt.?
 $$\left(A\right)$$ $$A{g}_{2}S$$
$$\left(B\right)$$ $$Ag{S}_2{O}_3$$
$$\left(C\right)$$ $$A{g}_2{S}_2{O}_3$$
$$\left(D\right)$$ $$AgN{O}_3$$

Answer 1

Hint: The question is easy once we go through the definition of white precipitate . Crystalline compound $$Hg{\left(N{H}_3\right)}_{2}C{l}_2$$ is normally made by mixing a mercuric chloride solution with a hot solution of ammonia and ammonium chloride.

Complete answer:
$$\left(C\right)$$$$A{g}_{{}_{{}_2}}{S}_2{O}_3$$
When Silver nitrate and sodium thiosulfate reacts, a white precipitate is formed.
$$2A{g^{+}}_{\left(aq\right)}+S_2{O}_3{}_{\left(aq\right)}^{2-}\to A{g}_2{S}_2{O_3}_{\left(s\right)}$$
In plant cell cultures, silver thiosulfate (STS) is widely used to inhibit the action of ethylene. Ethylene is a hormone that exists in a gaseous form. Ethylene levels have been shown to rise in plant cell cultures due to wounding or the presence of auxins during senescence and ripening.
Silver thiosulfate is more technique-dependent, but it's only used about every five days. So more work and caustic chemicals were needed, which were precisely measured up front but only reapplied every 5 days for a total of 30 days. Colloidal silver can be produced cheaply and safely using electrolysis (I need to research the process).
Silver thiosulfate is good only when it is stored at $$2-8^{\circ }C$$ . It’s shelf life is about 30 days .If not stored properly it can be spoiled and will be of no use. Proper storage is very important in case of silver thiosulfate.

Note:
Method of using Silver Thiosulfate is to Add your Silver Thiosulfate to 400ml of distilled water, so you'll have around 450ml of STS. Make sure to shake quite a lot until it's completely mixed. It's still much too concentrated to apply straight onto your plants; take 100ml of the mixture you just made and add it to 400ml more of distilled water.