Block 1 Flashcards
What are the 3 ways we look at a chemical reaction
- Observe
- Particulate (Think about the reaction and what’s happening at the molecular level)
- Symbolic
As chemists how should we view a chemical reaction
We should Particulate aka think about the reaction and what’s happening at the molecular level
Who is J.J Thomsom and what did he do?
He is a British Physicist from Cambridge. His research in cathode rays led to the discovery of the electron, and he pursued further innovations in atomic structure exploration.
What are canal rays?
Also called an anode ray, they are a beam of positive ions that is created by certain types of gas-discharge tubes
What are cathode rays?
A cathode ray is a beam of electrons in a vacuum tube traveling from the negatively charged electrode (cathode) at one end to the positively charged electrode (anode). They are also called electron beams.
What are Cathode ray tubes?
The cathode-ray tube is a vacuum tube that contains one or more electron guns and a phosphorescent screen and is used to display images. It modulates, accelerates, and deflects electron beam onto the screen to create the images..
Why is the Charge to Mass ratio (e/m) important?
Knowing the charge to mass ratio allows us to calculate the mass of the electron or proton by measuring charge effects. … Since the force on a charged particle is proportional to its charge, the deflection of a beam of charged particles will be the same for all particles with the same charge to mass ratio.
True or False. Electrons are lighter and smaller than atoms?
True
What are the three most common types of radioactive emissions?
Beta (B), Alpha (a), and Gamma (y) *Letters do not exactly represent the symbol for these radioactive emissions.
What charge do alpha particles have?
They have a positive charge
What charge do Beta particles have?
They can either have a negative or a positive charge?
What charge do Gamma particles have?
They have no charge
If you were to have 3 substances: paper, 0.5cm lead, and 10cm led in a row, out of the 3 most common types of radioactive emissions which could reach the 10cm led?
Gamma rays (y)
What is a geiger counter?
A Geiger counter is an instrument used for detecting radioactive emissions, most commonly beta particles and gamma rays.
What is a scintillation counter?
A scintillation counter is an instrument for detecting and measuring ionizing radiation by using the excitation effect of incident radiation on a scintillating material, and detecting the resultant light pulses.
What is the difference between the gieger counter and the scintillation counter?
The GM counter can detect all kinds of radiations such as alpha, beta and gamma rays, whereas the scintillation counter can detect only ionizing radiations.
What is the bohr model and is it used in modern times?
In atomic physics, the Rutherford–Bohr model or Bohr model, presented by Niels Bohr and Ernest Rutherford in 1913, is a system consisting of a small, dense nucleus surrounded by orbiting electrons—similar to the structure of the Solar System. This model works easily in modern times with very simple atoms such as hydrogen although would be incorrect for other atoms these days and require another model.
What are ions?
Positively or negatively charged particles.
What is a mass spectrometer?
A mass spectrometer produces charged particles (ions) from the chemical substances that are to be analyzed. The mass spectrometer then uses electric and magnetic fields to measure the mass (“weight”) of the charged particles.
True or False Hydrogen does not have neutrons?
True.
Who discovered the neutron and in what year?
Chadwick (1932)
True or False neutron particles will have approximately the same mass as the proton of an atom.
True
How many atoms are in the human body?
7x10^27
Define atomic mass
Atomic mass is the mass of a single atom (its nuclei) of a chemical element. When calculating atomic mass the mass of electrons is negligible as its weight is too small to make a difference to our calculation.