Answer:
Never smoke near a place where hydrogen is generated or being used. Remove all possible sources of flame and sparks. Hydrogen should only be generated and used in a well ventilated out door area. Precautions must be taken to remove all possibilities of fire or explosion.
Answer:
V
Explanation:
Convection is single or multiphase fluid flow that occurs spontaneously due to the combined effects of material property heterogeneity and body forces on a fluid, most commonly density and gravity (see buoyancy). When the cause of the convection is unspecified, convection due to the effects of thermal expansion and buoyancy can be assumed. Convection may also take place in soft solids or mixtures where particles can flow.
The correct answer is
D burning wood
because it's changing the wood.
The other's are physical changes because it's still the same thing, it's just in a different form.
Glad I could help, and good luck!
AnonymousGiantsFan
58 ce is the correct answer!
H3O4 is your answer but u should use your chart
