John Dalton was a scientist who proposed that all matter consists of atoms. At this stage, no one had yet discovered neutrons and the nucleus. As a result, Dalton's model consisted of a single atom i.e. the atom was the smallest object.
A mass spectrometer is an instrument that is able to see what is inside an atom. Scientists have been able to prove that the item is not the smallest object in the world. Atoms are made up of smaller objects called protons, neutrons and electrons.
We can, therefore, safely conclude that data from mass spectrometry has helped modern scientists to make modifications to Dalton's model. <span>
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Answer:
The chronic daily intake during the period of exposure is most nearly 0.012 mg/kg day.
Explanation:
Number of hours worker exposed to xylene = 
The concentration of xylene in the workplace =
The worker is inhaling air at a rate of 
.
Amount xylene inhaled by worker in an hour :
= 
Amount xylene inhaled by worker in 320 hours:
1 μg = 0.001 mg
Amount xylene inhaled by worker in 320 hours = 11.520 mg
1 day = 24 hours
Amount xylene inhaled by worker in 1 day:
Assuming 70 kg body mass, the chronic daily intake of xylene :
The chronic daily intake during the period of exposure is most nearly 0.012 mg/kg day.
Sonia observed that the two balloons repelled each other. This is because both balloons acquired the same charge when she rubbed them with the piece of wool, and like charges repel each other.
5.2 km to mm.
1km = 1000m
= 5.2 * 1000m.
=5200 m. 1m = 1000mm
= 5200 * 1000mm
= 5200000 mm
Answer: Ions may be defined as the element that contains either positive or negative charge over them. Two types of ions are cations and anions. The outermost electrons are involved in the formation of ions.
The atomic number of sulfur is 16. Its outermost electronic configuration is K=2, L= 8, M= 6. The sulfur requres two more electrons to complete its orbit and accquire -2 charge.
Explanation:
