1 it a 2 it b 3 it c 4 it be 7 it a
Answer:
Here
Explanation:
Chemists need the mole concept to bridge the gap between the microscopic world of atoms to the macroscopic world of humans. As you know, the molecular level consists of particles that are invisible to us.
Answer:
This question is incomplete; the complete part is:
A) All cell have a cell wall.
B) All cell arise from pre-existing cells.
C) All cell are capable of photosynthesis.
D) All cell can develop into any other type of cell.
The answer is B
Explanation:
The commonly known universal theory proposed in 1838 took the contribution from three remarkable scientists namely: botanist Matthias Schleiden, anatomist Theodor Schwann and biologist Rudolph Virchow. According to the question, Mathias discovered that all plants are made of cells, Schwann determined that all animals are made of cells while Virchow determined that all living things are composed of cells.
However, in addition to Virchow's discovery, he also discovered and proposed that "All cell arise from pre-existing cells", which till date forms part of the three components of the cell theory. The three parts are:
- Cell is the fundamental and basic unit of all living things.
- All living things are made up of one or more cells
- All cells arise from pre-existing cells
Answer: The given statement is false.
Explanation:
Precipitation reaction is defined as the chemical reaction in which two aqueous solution upon mixing together results in the formation of an insoluble solid.
For example, 
Here AgCl is present in solid state so, it is the precipitate.
But it is not necessarily true that two aqueous solutions will always result in the formation of a precipitate.
For example, 
Hence, we can conclude that the statement precipitation reactions always occur when two aqueous solutions are mixed, is false.
