Which inorganic compound can act as semipermeable membrane?Calcium sulphateBarium oxalateNickel phosphateCopper ferrocyanide

To determine which inorganic compound can act as a semipermeable membrane, we need to understand the properties of each compound listed: calcium sulphate, barium oxalate, nickel phosphate, and copper ferrocyanide.

1. Calcium sulphate: Calcium sulphate, also known as gypsum, is commonly used in construction materials and as a food additive. However, it does not possess the necessary properties to act as a semipermeable membrane.

2. Barium oxalate: Barium oxalate is a white crystalline compound that is sparingly soluble in water. It is primarily used in analytical chemistry and as a precursor for other barium compounds. However, it does not have the characteristics of a semipermeable membrane.

3. Nickel phosphate: Nickel phosphate is an inorganic compound that can be found in various forms, such as nickel(II) phosphate and nickel(III) phosphate. It is used in the production of ceramics, catalysts, and batteries. However, it does not possess the properties required for a semipermeable membrane.

4. Copper ferrocyanide: Copper ferrocyanide, also known as cupric ferrocyanide or copper(II) hexacyanoferrate(II), is a blue crystalline compound. It is used as a pigment in paints and dyes. However, it does not have the necessary characteristics to act as a semipermeable membrane.

Based on the properties and uses of these compounds, none of them can act as a semipermeable membrane.