Answer:
The modern periodic law states that the physical and chemical properties of the elements are the periodic function of the atomic numbers and electronic configurations. ... This repetition occurs if the arrangement of the elements is in order of their increasing atomic numbers.
Answer:
Energy should be saved and controlled as it is better for the environment. Excess use of energy of any kind can be disastrous. For example, a kind of energy is stored in the food. If excess food is consumed and wasted, then the country and other people will have to face consequences of it. Malnutrition will rise.
Another kind of energy is the energy in the fuel. If fuel consumption is not controlled then in the near future the resources for the making of fuel will be depleted.
Density=mass/volume
Data:
mass=890 g
volume=100 cm³
Density=890 g/100 cm³=8.9 g/cm³
answer: the density of the copper is 8.9 g/cm³
Aluminium isn’t a compound as it is an element