Answer:
Explanation:
<u>Problem</u>:
In a gender based experiment, the blood pressure of different ages of men is been checked and recorded to determine if there is any correlation. What will be the independent, dependent and controlled variables?
<u>Answer</u>:
A controlled variable is the variable that is left constant throughout the course of an experiment. The controlled variable here is the gender.
A dependent variable is the variable that is been determined or measured during the course of an experiment. The dependent variable here is the blood pressure.
An independent variable is the variable that is intentionally or decidedly altered during the course of an experiment. The independent variable here is the age.
Answer:
(1)There are 1.5 moles of water in a 27 gram sample of water. The molar mass of water is 18.02 gmol g m o l .(2)
AnswersChemistryGCSEArticle
What is the mass (g) of 0.25mols of NaCl?
What you need for these equations are a calculator, periodic table and the following equation:
Mass (g) = Mr x Moles (important equation to remember)
In this case we already know the moles as it's in the question, 0.25 moles.
to find the Mr, you need to look at your periodic table. Find the relative atomic mass of Na and Cl and add the two numbers together.
Na = 22.99
Cl = 35.45
NaCl = 58.4
Now just put all of the numbers into the equation.
0.25 x 58.4 = 14.6g
I am pretty sure it is B. If it turns litmus paper red it is acidic. The other 2 make no sense.
I might be wrong tho.
Hope that helped☺️
Answer: The capillary rise(h) in the glass tube is = 0.009m
Explanation:
Using the equation
h = 2Tcosθ/rpg
Given
Contact angle, θ = Zero
h = height of the glass tube=?
T = surface tension = 
r = radius of the tube = 0.1mm =0.0001m
p= density of ethanol = 
g= 
h = 
h= 0.09m
Therefore the capillary rise in the tube is 0.09m
