The right option is; a pure substance and an element.
A piece of sodium metal can be described as a pure substance and an element.
Sodium is a chemical element with an atomic number of 11. Sodium is a soft, waxy, silvery, highly reactive metal. Sodium belongs to group 1 of the periodic table and it is highly abundant in the earth’s crust. Sodium can also be found in various minerals such as rock salt, feldspars and sodalite.
The molar concentration of the solution is calculated as follows
find the moles of NaCl used to make the solution
moles = mass/molar mass
mass =7.83 g
molar mass =58.5 g/mol
moles = 7.83 g/ 58.5 g/mol = 0.134 moles
molarity ( concentration in mol/l) = number of moles/volume in liters
volume in liters = 90ml/1000 =0.09 liters
molarity is therefore = 0.134 moles/0.09 L =1.49 M
Answer:
mass of one carbon atom = g
Explanation:
1 mole of carbon contains atoms of carbon
therefore mass of atoms of carbon is 12.011 grams. therefore mass of one carbon atom will be g
mass of one carbon atom = g
Answer:
B. conducting a scientific experiment
Explanation:
The formulation of a hypothesis which is usually a scientific explanation usually leads to the process of carrying out experiments.
Scientific methods are systematic ways in scientists seeks to explain observations.
After a hypothesis is formulated, it is then tested using different experiments to ascertain its correctness and the extent of its reliability. A hypothesis must be testable.