Answer:
(a) adding 0.050 mol of HCl
Explanation:
A buffer is defined as the mixture of a weak acid and its conjugate base -or vice versa-.
In the buffer:
1.0L × (0.10 mol / L) = 0.10 moles of HF -<em>Weak acid-</em>
1.0L × (0.050 mol / L) = 0.050 moles of NaF -<em>Conjugate base-</em>
-The weak acid reacts with bases as NaOH and the conjugate base reacts with acids as HCl-
Thus:
<em>(a) adding 0.050 mol of HCl:</em> The addition of 0.050moles of HCl produce the reaction of 0.050 moles of NaF producing HF. That means after the reaction, all NaF is consumed and you will have in solution just the weak acid <em>destroying the buffer</em>.
(b) adding 0.050 mol of NaOH: The NaOH reacts with HF producing more NaF. Would be consumed just 0.050 moles of HF -remaining 0.050 moles of HF-. Thus, the buffer <em>wouldn't be destroyed</em>.
(c) adding 0.050 mol of NaF: The addition of conjugate base <em>doesn't destroy the buffer</em>
Answer: -
1) 8.33 minutes
2) 118.39 in/ s
180.43 m/min
10.83 km/ hr
Explanation: -
Speed of light = 3 x 10⁸ m/s
Distance of the earth from the sun= 93 million miles
We know 1 million = 1,000,000
Also 1 mile = 1609 m
Distance of the earth from the sun= 93 million miles
= 93,000,000 miles.
= 1.5 x 
m
Time taken = 
= ![\frac{1.5 x [tex] 10^{11}](https://tex.z-dn.net/?f=%20%5Cfrac%7B1.5%20x%20%5Btex%5D%2010%5E%7B11%7D%20%20)
m}{3 x 10⁸ m/s} [/tex]
= 500 s
= 500/ 60
= 8.33 minutes
2) Distance = 1 mile = 63360 inches
Time taken = 8.92 min
= 8.92 x 60
= 535.2 s
Speed = 
= 
= 118.39 in/ s
Distance = 1 mile = 63360 inches = 63360 x 2.54 cm = 63360 x 2.54 x 
m
Time taken = 8.92 min
Speed =
= ![\frac{63360 x 2.54 x [tex] 10^{-2}](https://tex.z-dn.net/?f=%20%5Cfrac%7B63360%20x%202.54%20x%20%5Btex%5D%2010%5E%7B-2%7D%20%20)
m}{8.92 min} [/tex]
= 180.43 m/ min
1 m = 10⁻³ Km
1 min = 1/60 hour
1 m /min = 10⁻³ km/ 
= 60/1000
=0.06 km/hr
180.43 m / min = 180 x 0.06 km / hr
= 10.93 km / hr
Forming a covalent bond
A covalent bond is formed when two atoms share a pair of electrons. Covalent bonding occurs in most non-metal elements, and in compounds formed between non-metals.
These shared electrons are found in the outer shells of the atoms. Usually each atom contributes one electron to the shared pair of electrons.
The slideshow shows how a covalent bond forms between a hydrogen atom and a chlorine atom, making hydrogen chloride.
Structures of a hydrogen atom and a chlorine atom.
1. A hydrogen atom with one electron and a chlorine atom with 17 electrons
Molecules
Most covalently bonded substances consist of small molecules. A molecule is a group of two or more atoms joined together by covalent bonds. Molecules of the same element or compound always contain the same number of atoms of each element.
The atoms in a molecule are always joined together by a covalent bond. Substances that are made up of ions do not form molecules.
Sizes of atoms and simple molecules
A small molecule contains only a few atoms, so atoms and small molecules have a similar range of sizes. They are very small, typically around 0.1 nm or 1 × 10-10 m across.
Ps please mark me as brainiest please
Complete Question
Questions Diagram is attached below
Answer:
* 
* 
* 
Explanation:
From the question we are told that:
Temperature 
Pressure 
Volume
Generally the equation for gas Constant is mathematically given by
Therefore
Work-done
Generally the equation for internal energy is mathematically given by
Therefore
Answer:
<h3>The answer is 0.42 g/mL</h3>
Explanation:
The density of a substance can be found by using the formula
From the question
mass = 8.11 g
volume = final volume of water - initial volume of water
volume = 44.72 - 25.26 = 19.46 mL
We have
We have the final answer as
<h3>0.42 g/mL</h3>
Hope this helps you
