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.
Mass number = protons + neutrons. 12 + 11 = 23.
72g
Explanation:
Given parameters:
Number of moles of LiOH = 3moles
Unknown:
Mass of LiOH = ?
Solution:
A mole of substance is a unit used to make quantitative measures in chemistry.
It is the amount of substance that contains the avogadro's number of particles.
The mole is related to mass using the expression below;
Mass of a substance = number of moles x molar mass
Molar mass of LiOH = 7 + 16 + 1 = 24g/mol
Mass of LiOH = 3 x 24 = 72g
learn more:
Number of moles brainly.com/question/1841136
#learnwithBrainly
3rd option please and good luck hope you pass...........
Answer:
57.47 grams of sodium is in the sample.
Explanation:
Given that a 100.0-g sample of sodium hydroxide contains sodium, oxygen, and hydrogen, and the sample contains 2.53 g of hydrogen and 40.0 g of oxygen, to determine what mass of sodium is in the sample the following calculation must be performed:
100 - (40 + 2.53) = X
100 - 42.53 = X
57.47 = X
Therefore, 57.47 grams of sodium is in the sample.
