Elements C1

• What is an atom made up of?

  An atom is made up of a central nucleus comprising protons and neutrons, with electrons orbiting around it.
• What determines which element an atom is?

  The number of protons in the nucleus determines which element an atom is.
• What is the smallest element?

  The smallest element is hydrogen.
• How many protons does a hydrogen atom have?

  A hydrogen atom has one proton in its nucleus.
• What is the atomic structure of helium?

  Helium has two protons, two neutrons, and two electrons.
• How many different elements are there approximately?

  There are around 100 different elements.
• What does each box in the periodic table represent?

  • Each box represents a different element.
  • These boxes are called nuclear symbols.
• What does the number in the bottom left of a nuclear symbol represent?

  The number in the bottom left is the atomic number, which represents the number of protons in the atom.
• What is the atomic number of helium?

  The atomic number of helium is two.
• What is the atomic number of carbon?

  The atomic number of carbon is six.
• If an atom has three protons, what element is it?

  If an atom has three protons, it is lithium.
• What are isotopes?

  • Isotopes are different forms of the same element.
  • They have the same number of protons but a different number of neutrons.
• What is the most common form of carbon?

  The most common form of carbon is carbon-12.
• How many neutrons does carbon-12 have?

  Carbon-12 has six neutrons.
• What is the mass number of carbon-13?

  The mass number of carbon-13 is 13.
• How do isotopes chemically react?

  • Isotopes of an element react in basically the same way.
  • They only vary in the number of neutrons.
• What is relative atomic mass?

  Relative atomic mass is the average mass of all the isotopes that make up a particular element.
• What are the stable isotopes of copper?

  The stable isotopes of copper are copper-63 and copper-65.
• What does abundance mean in the context of isotopes?

  Abundance refers to how common or rare that isotope is.
• How do you calculate the relative atomic mass of copper?

  You multiply each isotope's abundance by its mass, sum these figures, and divide by the total abundance.
• What is the equation for relative atomic mass?

  The equation is the sum of isotope abundance times isotope mass divided by the sum of the abundances of all the isotopes.
• What is the first step in calculating the relative atomic mass of copper?

  The first step is to multiply each isotope's abundance by its mass.
• What is the total abundance of the two stable isotopes of copper?

  The total abundance of the two stable isotopes of copper is 100%.
• What is the relative atomic mass of copper rounded to one decimal place?

  The relative atomic mass of copper is 63.6.
• What symbol denotes relative atomic mass?

  The symbol that denotes relative atomic mass is \( \text{Ar} \).
• What does the average mass of a copper atom represent?

  The average mass of a copper atom represents its relative atomic mass.
• What should you do if you're unsure about a nuclear symbol on the periodic table?

  • Check the periodic table for the symbol.
  • Most periodic tables have both the symbol and the name.