Both A and D
Because these compunds of reactant and the compounds of the product . The reactant goint to equation
<u>Answer:</u> The symbol of the ion formed is 
<u>Explanation:</u>
An ion is formed when a neutral atom looses or gains electrons.
- When an atom looses electrons, it results in the formation of positive ion known as cation.
- When an atom gains electrons, it results in the formation of negative ion known as anion.
Electronic configuration is defined as the representation of electrons around the nucleus of an atom.
Number of electrons in an atom is determined by the atomic number of that atom.
The element present in Group 2-A and in period 4 is Calcium (Ca)
Electronic configuration of Ca atom: 
This atom will loose 2 electrons to attain stable electronic configuration similar to Argon element (noble gas)
The electronic configration of 
Hence, the symbol of the ion formed is 
Answer:
Solid Osmium transition metal reacts with Oxygen gas to produce solid Osmium tetroxide.
Os(s) + 2O₂(g) -> OsO₄(s)
Explanation:
Osmium tetroxide is another way of writing Osmium (VIII) oxide.
Leaving powdered osmium exposed to air in a room will slowly create osmium tetroxide at room temperature.
Similarly, osmium tetroxide vapor will readily be released from a liquid solution at room temperature.
Answer:
Top-Toluene
Middle-Water
Bottom-Chloroform
Explication:
Chloroform is on the bottom layer because it is the densest liquid.
Toluene is on the top because it is the least dense.
Water is between the two because it’s density is between chloroform and toluene.
Answer:
Alcohol and water.
Explanation:
Alcohol and water is a homogenous mixture. because these two liquids are soluble, miscible in all composition. A homogenous mixture is a solution that has equal composition of its components.
Irregular mixing of two liquid components have different refractive indexes. At a high temperature, it can become inhomogenous spontaneously.
A solution is a type of homogenous mixture which composed of two or more substances. In a mixture a solute is a substance, dissolves in other substance that is solvents like alcohol and water, alcohol is solute and water is a solvent.