A scientific model is a simplified version of some phenomenon that takes place in natural systems. A scientific model can be visual (flow charts), graphical, conceptual, or mathematical. These models are used to make predictions about how a set of conditions would change the present scenario in future. Scientific models can explain how the ongoing changes in the environment can show long term affect on our planet like the climate change. Therefore, a scientific model can be used to explain the phenomena like the effect of global air temperatures on the mean sea level around the world.
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.
Ca + 2HCl = CaCl₂ + H₂
c=4.50 mol/l
v=2.20 l
n(HCl)=cv
m(Ca)/M(Ca)=n(HCl)/2
m(Ca)=M(Ca)cv/2
m(Ca)=40g/mol·4.50mol/l·2.20l/2=198 g
198 grams of Ca are needed
Answer:
False
Explanation:
Always add acid to the water, it dilutes the acid the other way around.
You put in a variable to substitute the unknown number.