It is defined as the amount of a substance that contains as many particles as there are atoms in 12 grams of pure carbon-12. So, 1 molecule contains 6.022×10^23 elementary entities of the substance.
Hope that helps
Answer:
Discovery of electron while studying the properties of cathode ray by Thomson suggested that Dalton atomic model should be revised.
Explanation:
Electron was discovered by j. j. Thomson in 1897 during the study of cathode ray properties.
He constructed the glass tube and create vacuum in it. He applied electric current between electrodes. He noticed that a ray of particles coming from cathode to wards positively charged anode. This ray was cathode ray.
Properties of cathode ray:
The ray is travel in straight line.
The cathode ray is independent of composition of cathode.
When electric field is applied cathode ray is deflected towards the positively charged plate.
Hence it was consist of negatively charged particles.
Symbol= e-
Mass= 9.10938356×10-31 Kg
The electron is subatomic particle that revolve around outside the nucleus and has negligible mass. It has a negative charge.
Answer:
-125.4
Explanation:
Target equation is 4C(s) + 5H2(g) = C4H10
These are the data equations for enthalpy of combustion
- C(s) + O2(g) =O2(g) -393.5 kJ/mol * 4
- H2(g) + ½O2(g) =H20(l) = 285.8 kJ/mol * 5
- 2CO2(g) + 3H2O(l) = 13/2O2 (g) + C4H10 - 2877.1 reverse
To get target equation multiply data equation 1 by 4; multiply equation 2 by 5; and reverse equation 3, so...
Calculate 4(-393.5) + 5(-285.8) + 2877.6 and you should get the answer.
False! Primary succession is when a community has to completely start over which takes a long time.
