Answer:
A theory of chemical combination, first stated by John Dalton in 1803. It involves the following postulates: (1) Elements consist of indivisible small particles (atoms). (2) All atoms of the same element are identical; different elements have different types of atom. (3) Atoms can neither be created nor destroyed. Based on all his observations, Dalton proposed his model of an atom. It is often referred to as the billiard ball model. He defined an atom to be a ball-like structure, as the concepts of atomic nucleus and electrons were unknown at the time.
John Dalton developed a crude method for measuring the masses of the elements in a compound. His law of multiple proportions states that when two elements form more than one compound, masses of one element that combine with a fixed mass of the other are in a ratio of small whole numbers.
Explanation: Sup. Hope dis helps u bro
Hypothesis is a smart guess that you make on the result of your experiment. You make this even before doing the experiment through inferential analysis. If the hypothesis you made was that, cotton will grow larger balls, then in the experiment, you should measure the cotton boll's size. The size should be in terms of diameter. So, the answer is b.
It is an endothermic reaction because the products hAve more heat than the reactions so it was a gain of heat which makes the enthalpy Change positive !