Question 17:
False; cutting hair would change what it looks like but, braiding it keeps it the same substance it is.
Question 18 :
My best guess would either be A or D. I would lean more towards D because if there are different mixtures then it depends on what you are mixing.
Hope it helps in some way. <3
Answer:
heat from the sun and heat flowing out of earth as it cools.
Answer:
Im not really sure what a half life is, but two of them would be 5.0 hours
Answer:
Molar mass = 32.64 g / mol.
The density of gas is 1.3 × 10⁻³g/mL.
Explanation:
Given data:
Mass of sample = 2.35 g
Pressure = 1.05 atm
Volume = 1.85 L (1.85 × 1000 = 1850 ml)
Temperature = 55 °C (55+ 273.15 = 328.15 K)
Density = ?
Formula:
d = m/ v
The volume of flask would be the volume of gas.
d = 2.35 g / 1850 mL = 0.0013 g/mL or 1.3 × 10⁻³g/mL
The density of gas is 1.3 × 10⁻³g/mL.
Molar mass:
Now we will calculate the moles of a gas first in order to find the molar mass of a gas.
Formula:
PV =nRT
n = number of moles.
n = PV / RT
n = 1.05 atm × 1.85 L / 0.0821 atm. dm³. K⁻¹ . mol⁻¹ × 328.15 K
n = 1.9425 atm . L / 26.941115 atm . dm.³mol⁻¹
n = 0.072 mol
Now we will find the molar mass.
Number of moles = mass / molar mass
0.072 mol = 2.35 g / molar mass
Molar mass = 2.35 g / 0.072 mol
Molar mass = 32.64 g / mol
Answer:
The exception here is
C2 and B2
both the bonds are pi bond in the above cases
Explanation:
The fault here is the unforeseen energy order of molecular orbitals. Since if filled, sigma 2px will be firmly pushed away by the electron density of orbitals already filled with sigma 2s (both electron densities lie on the inter-nuclear axis). Because of this, sigma 2px's energy is found shockingly greater than pi 2py and pi 2pz.
The electrons therefore occupy pi 2py and pi 2pz orbitals as opposed to normal sigma 2px (which remains vacant) while filling.
The existence of these 4 electrons in orbitals pi 2py and pi 2pz results in two pi bonds being formed.
