Atoms

• how to find the protons?

  the bottom number of the element
• calculation for the number of neutrons?

  mass number- number of protons
• how to find the electrons?

  the same number of protons
• how small is an atom radius?

  1x10-10m
• how small is the radius of a nucleus?

  1x10-14m
• what is an element?

  substances made up of only 1 type of atom
• what is a compound?

  a substance containing 2 or more different elements chemically combined in fixed proportions
• balance H20---> H2 + O2?

  2H20-----> 2H2+O2
• Ammonia?


  NH3
• sulfuric acid?


  H2S04
• hydrochloric acid?


  HCL
• what are protons?

  + charged particles
• what are neutrons?

  no charge
• what are electrons?

  negatively charged particles in shells
• what is the relative charge of a proton?

  +1
• what is the relative charge of a neutron?

  0
• what is the relative charge of a electron?

  -1
• what is the relative mass of a proton?

  1
• what is the relative mass of a neutron?

  1
• what is the relative mass of a electrons?

  1/2000
• what is an isotope?

  atoms of the same element that have the same number of protons but a different number of neutrons
• what is an ion?


  a charged particle that is formed when an atom or molecule gains or loses electrons
• what is relative atomic mass?

  the average mass of all the atoms of an element compared ti the 1/12th the mass
• Calculate the relative atomic mass?

  • (7x6)+(7x96)/100 = 6.93

  
• what is a mixture?

  consists of 2 or more elements or compounds not chemically combined