Answer:
B
Explanation:
It is important to only test one variable at a time because you need to be able to disprove or prove a problem with just one independent variable. When you have several variables in the experiment, it would be impossible to know which variable honestly caused the end result.
The answer is B. A good way determine this is how far right the element is on the periodic table. The further right the element is, the more electronegative it is meaning it is more willing to accept an electron. This can be explained using the valence electrons and how many need to be added or removed to complete the octet. The further right you are, the easier it is for the element to just gain a few electrons instead of loose a bunch. Noble gases are the exception to this since they don't normally react though.
Answer: 4m/s2 (B)
Explanation:
Force = mass × acceleration
Force given is 8N
Mass=2kg
Acceleration =?
Substitute into the formula
F=ma
8=2a
A=8/2
A=4m/s2
Acceleration used is 4m/s2 (B)
Answer:
The molecular formula of X is C8H9NO2
Explanation:
Step 1: Data given
exact mass of 151.0640
Molar mass of C = 12 g/mol
Molar mass of H = 1.00783 g/mol
Molar mass of O = 15.9949 g/mol
Molar mass of N = 14.0031 g/mol
Step 2: Calculate molar mass of C7H5NO3
7*12 + 5*1.00783 + 14.0031 + 3*15.9949 = 151.02695 g/mol
Step 3: Calculate molar mass of C8H9NO2
8*12 + 9*1.00783 + 14.0031 + 2*15.9949 = 151.06337 g/mol
Step 4: Calculate molar mass of C10H17N
10*12 + 17*1.00783 + 14.0031 = 151.13621 g/mol
The molecular formula of X is C8H9NO2
Explanation:
The speed of molecules increases when temperature is increased as it will result in more number of collisions between the molecules. Thus, there will be increase in kinetic energy of molecules and increase in the speed of solvent molecules.
Whereas on decreasing the temperature, the kinetic energy of molecules will decrease. This will result in less number of collisions between the molecules. Therefore, the speed of solvent molecules will slow down.
