Answer:
A. LST
Explanation:
• 1st Law: The path of each planet around the Sun is an ellipse with the Sun at one focus.
• 2nd Law: The line from the Sun to any planet sweeps out equal areas of space in equal time intervals.
• 3rd Law: The square of the orbital period of a planet is directly proportional to the cube of the average distance
answer
When an electron temporarily occupies an energy state greater than its ground state, it is in an excited state. An electron can become excited if it is given extra energy, such as if it absorbs a photon, or packet of light, or collides with a nearby atom or particle
Answer:Aluminium is widely used in building because of its intrinsic properties of lightness and corrosion resistance. Aluminum is used in external facades, roofs and walls, in windows and doors, in staircases, railings, shelves, and other several applications.
Explanation:
HISTORICAL INTRODUCTION.1<span> EVER since the establishment of the atomic theory by Dalton and Berzelius it was felt among chemists that there must be some relation between the atomic weights of the different elements and their properties. It was recognized very early that there exist groups of elements possessing related chemical and physical properties, and one of the earliest attempts to bring out this point is due to Dobereiner. In 1829 he tried to show that “many elements may be arranged in groups ()f three, in each of which the middle element has an atomic weight equal or approximately equal to the mean of the atomic weights of the two extremes.” As illustrations of this method of arrangement may be mentioned the following groups: Li, Na, K; Ca,Sr,</span>
