Answer:
- Question 19: the three are molecular compounds.
Explanation:
<em>Question 19.</em>
All of them are the combination of two kinds of different atoms in fixed proportions.
- C₂H₄: two carbon atoms per four hydrogen atoms
- HF: one hydrogen atom per one fluorine atom
- H₂O₂: two hydrogen atoms per two oxygent atoms
Thus, they all meet the definition of compund: a pure substance formed by two or more different elements with a definite composition.
Molecular compounds are formed by covalent bonds and ionic compounds are formed by ionic bonds.
Two non-metal elements, like H-F, C - C, C - H, H-O, H - H, and O - O will share electrons forming covalent bonds to complete their valence shell. Thus, the three compounds are molecular and not ionic.
<em>Question 20. </em>Formula of copper(II) sulfate hydrate with 36.0% water.
Copper(II) sulfate is CuSO₄. Its molar mass is 159.609g/mol
Water is H₂O. Its molar mass is 18.015g/mol
Calling x the number of water molecules in the hydrate, the percentage of water is:

From which we can solve for x:

Thus, there are 5 molecules of water per each unit of CuSO₄, and the formula is:
Answer:
Coefficient of 
Coefficient of
=8
Explanation:
We are given that a reaction in which
reacts with 
We have to find the coefficient of each reactants in balanced reaction

Coefficient is defined the constant value multiplied with a reactant in a reaction.
Coefficient of
=3
Coefficient of 
Coefficient of 
Coefficient of 
Coefficient of 
Coefficient of KOH=2
Hence, Coefficient of
and coefficient of 
Answer:
The 2.8 hrs one i think???
hope this helps
Explanation:
Answer:
The volume is 19.7 mL
Explanation:
<u>Step 1</u>: Given data
Pressure at sea level = 1.00 atm
Pressure at 50 ft = 2.47535 atm
kH for N2 in water at 25°C is 7.0 × 10−4 mol/L·atm
Molarity (M) = kH x P
<u>Step 2</u>: Calculate molarity
M at sea level:
M = 7.0*10^-4 * (1.00atm * 0.78) = 5.46*10^-4 mol/L
M at 50ft:
M = 7.0*10^-4 * (2.47535atm * 0.78) = 13.5*10^-4 mol/L
We should find the volume of N2. To find the volume whe have to find the number of moles first. This we calculate by calculating the difference between M at 50 ft and M at sea level.
13.5*10^-4 mol/L - 5.46*10^-4 mol/L = 8.04*10^-4 mol/L
Step 3: Calculate volume
P*V=nRT
with P = 1.00 atm
with V = TO BE DETERMINED
with n = 8.04*10^-4 mol/L *1L = 8.04*10^-4
with R= 0.0821 atm * L/ mol *K
with T = 25 °C = 273+25 = 298 Kelvin
To find the volume, we re-organize the formula to: V=nRT/P
V= (8.04*10^-4 mol * 0.0821 (atm*L)/(mol*K)* 298K ) / 1.00atm = 0.0197L = 19.7ml
The volume is 19.7 mL