Answer:
(1) atomic numbers
Explanation:
The observed regularities in the properties of the elements on the periodic table are periodic functions of their atomic numbers.
- Atomic number is the number of protons in an atom.
- The periodic law states that "the properties of elements are a periodic function of their atomic number".
- Elements on the periodic table are arranged based on the atomic numbers they contain.
- The number of positively charged particles in an atom is the atomic number.
Answer:
The individual substances in a mixture can be separated using different methods, depending on the type of mixture. These methods include filtration, evaporation, distillation and chromatography.
Explanation:
Because water is polar and oil is nonpolar, their molecules are not
attracted to each other. The molecules of a polar solvent like water are
attracted to other polar molecules, such as those of sugar. This explains
why sugar has such a high solubility in water. Ionic compounds, such
as sodium chloride, are also highly soluble in water. Because water
molecules are polar, they interact with the sodium and chloride ions.
In general, polar solvents dissolve polar solutes, and nonpolar solvents
dissolve nonpolar solutes. This concept is often expressed as “Like
dissolves like.”
So many substances dissolve in water that it is sometimes called
the universal solvent. Water is considered to be essential for life
because it can carry just about anything the body needs to take in
or needs to get rid of.
Answer:
Distance cover = 8 km
Explanation:
Given:
Speed of runner = 4 km/h
Time taken = 2 hour
Find:
Distance cover
Computation:
Distance = Speed x Time
Distance cover = Speed of runner x Time taken
Distance cover = 4 x 2
Distance cover = 8 km
