1. The presence or absence of oxygen in the materials may result in the
A burning of the materials
B. melting of the materials
C. change in the materials
D. materials remain the same
2. Iron, nails, cans and other metals with iron when exposed to moisture may develop
A. dust
Brust
C. heat
D. fuel
3. The inner part of the potatoes and apples change in color because of
A fucl in it
B. chemicals in it
C. exposure to heat
D. exposure to oxygen
4. The process of burning materials with the aid of oxygen is
A conduction
B. combustion
C. oxidation
D. reduction
5. The Bureau of Fisheries investigated that fish kill incident was due to
A lack of oxygen supply
B. hot summer temperature
C. use of illegal fishing methods
D. lack of carbon dioxide supply
6. The factors that influence the formation of rust on iron are
A. increased level of oxygen
B. moisture and oxygen
C. dropping of oxygen
D. oxygen level
7. The absence of oxygen in lighting a candle will cause the candle's flame to
A burn
B. flare
C. ignite
D. extinguish
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