Answer:
Explanation:
Dalton's atomic theory proposed that all matter was composed of atoms, indivisible and indestructible building blocks. While all atoms of an element were identical, different elements had atoms of differing size and mass.
In 1897, J.J. Thomson discovered the electron by experimenting with a Crookes, or cathode ray, tube. He demonstrated that cathode rays were negatively charged. In addition, he also studied positively charged particles in neon gas.
Rutherford overturned Thomson's model in 1911 with his well-known gold foil experiment in which he demonstrated that the atom has a tiny and heavy nucleus. Rutherford designed an experiment to use the alpha particles emitted by a radioactive element as probes to the unseen world of atomic structure.
The Bohr model shows the atom as a small, positively charged nucleus surrounded by orbiting electrons. Bohr was the first to discover that electrons travel in separate orbits around the nucleus and that the number of electrons in the outer orbit determines the properties of an element.
Answer:
See below.
Explanation:
pH = - log (H+)
So the pH of 1 x 10^-7 M solution is 7.
I'm sorry but I'm not sure about what the other units mean, so Im not sure of the answer to those.
If you convert the other units to the form 1 x 10^-n then the pH will be n.
Answer:
464.1 J absorbed.
Explanation:
Given data:
Specific heat of zinc = 0.39 J/g°C
Mass of zinc = 34 g
Temperature changes = 22°C to 57°C
Energy absorbed or released = ?
Solution:
Formula:
Q = m.c. ΔT
Q = amount of heat absorbed or released
m = mass of given substance
c = specific heat capacity of substance
ΔT = change in temperature
ΔT = 57°C - 22°C
ΔT = 35°C
Q = m.c. ΔT
Q = 34 g. 0.39 J/g°C. 35°C
Q = 464.1 J
I believe the correct answer is the second option. The type of decay that characterizes the change of nuclides to their respective daughter products would be exponential decay. This type of decay is characterized by the decrease of quantity of a material according to the equation y=ab^x.
Answer:
Chitin
Explanation:
A fly's main body is made of a thorax and an abdomen. These parts are covered by a hard exoskeleton made of a bony substance called chitin.
