Answer:
It results from microscopic bumps and ridges
It causes a change in motion
It is opposite to the direction of the motion.
It is parallel to the surfaces that rub together.
Explanation:
Answer:
the second one looks balanced but I could be wrong
Answer:
B
Explanation:
Firstly, we will need to calculate the number of moles. To do this, we make use of the ideal gas equation
PV = nRT
n = PV/RT
The parameters have the following values according to the question:
P = 780mmHg, we convert this to pascal.
760mHG = 101325pa
780mmHg = xpa
x = (780 * 101325)/760 = 103,991 Pa
V= 400ml = 0.4L
T = 135C = 135 + 273.15 = 408.15K
n = ?
R = 8314.463LPa/K.mol
Substituting these values into the equation yields the following:
n = (103991 * 0.4)/(8314.463 * 408.15)
= 0.012 moles
Now we know 1 mole contains 6.02 * 10^23 molecules, hence, 0.012moles will contain = 0.012 * 6.02 * 10^23 = 7.38 * 10^21 molecules
Answer:
1. 266.22 g/mol
2. 168.81 g/mol
3. 223.35 g/mol
4. 199.88 g/mol
Explanation:
For you to calculate the molar mass of the salt you need to sum the molar masses of every element in the salt.
In the first salt, PdBr
, the subscript 2 means that there are 2 atoms of Br. So for you to calculate the molar mass of the salt you need to sum the molar mass of Pd and 2 times the molar mass of Br, as follows:
106 g/mol + 2(79.90 g/mol) = 266.22 g/mol
In the second salt BeBr
there are 2 atoms of Br and 1 of Be, so the molar mass is:
9.012 g/mol +2(79.90 g/mol) = 186.22 g/mol
In the third salt CuBr
there are 2 atoms of Br and 1 of Cu, so the molar mass is:
63.55 g/mol + 2(79.90 g/mol) = 223.35 g/mol
And in the fourth salt CaBr
there are 2 atoms of Br and 1 of Ca, so the molar mass is:
40.08 g/mol + 2(79.90 g/mol) = 199.88 g/mol
After reacting, place a red moist litmus paper into the final solution and the litmus paper will turn blue. This indicates that the solution is alkaline.
Alternative methods
Using universal indicator
using phenophtalein
using bromothyl blue
using methyl orange
use pH probe connected to a data logger