Answer:
b.open flame because it is fundamental end of the alcohol mixes in with the flame then it will become a bigger fire
They should identify the confounding variable.
Some condition that is not examined by the scientist might alter the experiment result. That condition is called confounding variable. If the method of the experiment same but result is very different, there should be unidentified confounding variable. It could be air humidity, temperature, ventilation, light, time of the year or anything that might not be seen by naked eye.
Try to redo the experiment with controlling variable as much as possible.
17) 8.4 / 20 x 100
18) 20 . 0.5150
19) 6,50% because (as you said) the law of definite proportions states that regardless of the amount, a compound is always composed of the same elements in the same proportion by mass
Answer:
The correct answer is 0.0033 L (33.0 mL)
Explanation:
We uses the Charles's law which describes the changes in the volume (V) of a gas and its temperature in Kelvin (T) at constant pressure. The mathematical expression is the following:
V₁/T₁ = V₂/T₂
We have the following data:
V₁= 31.0 mL = 0.0031 L
T₁= 19.0°C = 292 K
T₂= 38.0°C = 311 K
V₂= ?
We calculate V₂ from the mathematical expression, as follows:
V₂= V₁/T₁ x T₂ = 0.0031 L/(292 K) x 311 K = 0.0033 L
Distance and time is needed for determining speed
