Question

name: 2.03 exit ticket/homework. working silently and independently, answer the following questions on atoms, elements, compounds and mixtures. 1) democritus proposed that: a. all atoms of an element are positively charged b. different elements can have the same mass c. atoms of a given element must be identical d. all the atoms in a compound are identical. 2) daltons atomic theory states that: a. all atoms of an element are positively charged b. different elements can have the same mass c. atoms of a given element must be identical d. all the atoms in a compound are identical. 3) j. j. thomsons cathode ray tube experiment contributed to the development of which atomic model? a. wave mechanical model b. atom as hard sphere model c. plum pudding model d. empty space model 4) below and on the following page, determine if each picture is an element, a compound or a mixture. circle the correct answer. if it is a mixture specify whether it is a mixture of elements, a mixture of compounds or a mixture of both. element(s) compound(s) mixture of elements mixtures of compounds mixture of elements and compounds element(s) compound(s) mixture of elements mixtures of compounds mixture of elements and compounds

Explanation:

1. Democritus proposed that atoms of a given element must be identical. He believed atoms were indivisible and the fundamental building - blocks of matter.
2. Dalton's atomic theory stated that atoms of a given element must be identical. He also proposed other postulates like atoms combine in simple whole - number ratios to form compounds.
3. J.J. Thomson's Cathode Ray Tube experiment led to the development of the Plum Pudding Model, where electrons were thought to be embedded in a positively - charged sphere.
4. Without seeing the actual pictures, in general, an element consists of only one type of atom, a compound consists of two or more different types of atoms chemically bonded, and a mixture contains two or more substances (either elements or compounds) physically combined.

Answer:

1. c. atoms of a given element must be identical
2. c. atoms of a given element must be identical
3. c. Plum Pudding Model
4. Cannot be answered without seeing the pictures.