1. The air hole is _____________ after the bunsen burner is moved beneath the gauze in the tripod stand.
2. The flame is now colored ____________ as seen in the photograph.
3. The asbestos on the gauze colored __________________ is a good _____________ of heat and therefore conducts all the heat above and spreads the heat evenly to the glass beaker placed above it.
4. If the flame is very big the ____________ is turned so that only a smaller amount of gas is going to be burnt.