Science Yearly - Year 10 Term 4

Conservation of mass

Mass is neither created or destroyed in a reaction

Closed vs Opened System

A closed system means nothing can get in or out, for example a sealed flask. So the mass stays the same.

An opened system means gas can escape or come in so there seems to be extra or missing mass, which is just in the air

Ionic Compound

Is an element which is a positive metal element plus a negative non-metal element and the total charge has to be 0.

what does the superscript and subscript of a chemical formula mean?

The superscript is the ionic charge
the subscript is the numbe rof atoms

How to write an ionic formula

write the ions with their charges
give the first ion’s superscript to the second ion and the second ion’s superscript to the first ion and write them as a subscript and remove ± signs

write the ions next to each other, don’t write a 1
simplify if subscripts can be divided by same number.

Naming ionic compounds

Say the first element normally, then the second one you say the first syllable and then add ‘ide’ to the end. E.G: NaCl is Sodium Chloride

Balancing equations