I need details to solve for you
The enthalpy change for melting ice is called the entlaphy of fusion. Its value is 6.02 kj/mol. This means for every mole of ice we melt we must apply 6.02 kj of heat. We can calculate the heat needed with the following equation:
Q = N x ΔH
where:
Q = heat
N = moles
ΔH = enthalpy
In this problem we would like to calculate the heat needed to melt 35 grams of ice at 0 °C. This problem can be broken into three steps:
1. Calculate moles of water
2. multiply by the enthalpy of fusion
3. Convert kJ to J.
Step 1 : Calculate moles of water
![[ 75g ] x (\frac{1 mol}{18.02g} ) =](https://tex.z-dn.net/?f=%5B%2075g%20%5D%20x%20%28%5Cfrac%7B1%20mol%7D%7B18.02g%7D%20%29%20%3D)
Step 2 : Multiply by enthalpy of fusion
Q = N × ΔH = <em> [ Step 1 Answer ]</em> × 6.02 =
Step 3 : Convert kJ to J
![[ Step 2 Answer ] x (\frac{1000j}{1kJ} ) =](https://tex.z-dn.net/?f=%5B%20Step%202%20Answer%20%5D%20x%20%28%5Cfrac%7B1000j%7D%7B1kJ%7D%20%29%20%3D)
Finally rounding to 2 sig figs (since 34°C has two sig figs) we get
Q Would Equal ____
Answer:
The right choice is c. Water molecules have a weakly positive hydrogen end.
Explanation:
The unequal sharing of electrons in water molecule gives a slight negative charge near its oxygen atom ( see image below) and a slight positive charge near its hydrogen atoms. A neutral molecule that has a partial positive charge at one end and a partial negative charge at the other, it is a polar molecule.
so
a. Water molecules have a nonpolar bond.
It is wrong choice because water has polar bond .
b. Water molecules have a weakly positive oxygen end.
Also, a wrong choice due to water molecule gives a slight negative charge near its oxygen atom.
c. Water molecules have a weakly positive hydrogen end.
This is the right choice.
d. Water molecules have two oxygen and two hydrogen atoms
It is wrong choice because water has one oxygen and two hydrogen atoms
So, the right choice is
c. Water molecules have a weakly positive hydrogen end.
Answer:
The octet rule means that atoms need a total of 8 valence electrons to fill their valence shell. Hydrogen only needs two to fill its valence shell.
Explanation:
All atoms except for hydrogen can hold a total of 8 valence electrons in their outer energy levels (2 in the s level, 6 in the p level). Hydrogen only has two electrons total, so it does not require more than the s level and two electrons to have a full valence.