Answer:
Option c and d
Explanation:
John Dalton. In 1808, John Dalton proposed a theory known as Dalton’s Atomic Theory. The theory was published in a paper titled “A New Chemical Philosophy”. This theory was new to that era
The 5 postulates of Daltons' atomic theory are:
1. All the matters are made of atoms.
2. Atoms of different elements combine to form compounds
3. Compounds contain atoms in small whole-number ratios
4. Atoms can neither be created nor destroyed
. (This was later proven wrong )
5. All atoms of an element are identical and have the same properties (This was later proven wrong as atoms of same element may be different in case of elements having isotopes )
Therefore, options c and d are the answer.
Answer:
we can reach the same conclusions by applying different experimental and observational procedures
Explanation:
The scientific method is a process that can be summarized in the following steps: 1-to raise a question, 2-to make a hypothesis, 3-to obtain data from observations and/or experiments, and finally, 4-to obtain conclusions that enable to confirm (or reject) the hypothesis. The scientific method is flexible because it is not necessary to follow 'stringent' guidelines in order to reach the same conclusions. In consequence, the predictions derived from such results can be tested again to determine the veracity of the results.
2.a)R b)R c)L d)L e)R f)L g)L
Answer:
The atomic mass of Si-30 is 29.955 amu
Explanation:
Step 1: Data given
Si-28 has an atomic mass of 27.9769 amu and a natural abundance of 92.2 %
Si-29 has an atomic mass of 28.9765 amu and a natural abundance of 4.67%
The atomic mass of Si is 28.0855 amu
Step 2: Calculate natural abundance of Si-30
100% - 92.2 % - 4.67% = 3.13 %
0.922 * 27.9769 + 0.0467 * 28.9765 + 0.0313* X = 28.0855
27.14790435 + 0.0313X = 28.0855
0.0313X = 0.93760
X = 29.955 amu
The atomic mass of Si-30 is 29.955 amu