Answer: D
Explanation:
A control group is the variable that remains constant throughout the whole experiment
Answer:
Exothermic.
Explanation:
Exothermic is when he leaves the system. A way to remember is the "ex" which is a prefix/root/suffix or something that pretty much means leaving, I think. For example how it's in "Exodus" and "Exit", I think.
Endothermic is when it goes into the system. Similar to "ex" but with inside, I think. For example how it's in "Endoskeleton", I suppose.
Given:
n = 0.0021 mol
M = 44 gram/mol
Required: m or the mass of the molecule
Solution:
M = m/n
Rearranging the expression,
m = M x n
m = 44 g/mol x 0.0021 mol
Evaluating the expression and cancelling units, we obtain,
m = 0.0924 grams
M is the molar mass. This value is very useful in chemistry calculations especially in calculating the amounts of reactants and products for a chemical reaction.
Answer:
molality = 0.564 m
Explanation:
Molality = number of moles of solute / kg of solvent
1- getting moles of solute:
number of moles = mass / molar mass
we have:
mass = 373.5 g
molar mass = 331.2 g/mol
Therefore:
number of moles = 373.5 / 331.2 = 1.128 moles
2- getting kg of solvent:
mass in kg = mass in grams * 10⁻³
mass in kg = 2 * 10³ * 10⁻³
mass in kg = 2 kg
3- getting molality:
Molality = number of moles of solute / kg of solvent
Molality = 1.128 / 2
Molalty = 0.564 m
Hope this helps :)
Answer:
hello pls help me in this question
With determination and hard work, people can overcome difficult challenges. How do the people of Greensburg, Kansas, and Chicago, Illinois, illustrate this idea? Use details from both texts to support your response. i cant do it
Explanation: