Answer:
d. 1.2 × 1024
Explanation:
From the equation of reaction
2H2 + O2= 2H2O
i.e 2mole(4g) of hydrogen requires 1 mole(32g) of oxygen to produce 2mole (2×6.02×10^23 molecules) of H2O= 1.2×20^24 molcules of water.
NB: 1 mole of H2O contains 6.02×10^23 molecules of H2O
Answer:
Molecules move freely around since they don't have a definite shape. This is the reason water stays liquid and couldn't be gripped.
The material needed to stop a beta particle is c. thin pieces of wood.
Answer:
huhuhuhuhuhuhuhhihihihuhuhuhjgjfngnvnffv 42.6j
Explanation:
Answer:
78.7
Explanation:
The number has 4 significant figures: 7,8 6 and 5.
To round off to 3 significant figures, the target digit is the third significant figure in the number.The determining digit is the fourth significant figure in the number; it is 5 hence the target digit will go up by 1 and any digits to the right of it will be rounded down to 0.
