[H_{3}O^{+}] = 0.00770 M
The equilibrium equation representing the dissociation of 
Given [H_{3}O^{+}] = 0.00770 M
Let the initial concentration of acid be x and change y
So y = ![[H_{3}O^{+}]](https://tex.z-dn.net/?f=%20%5BH_%7B3%7DO%5E%7B%2B%7D%5D%20%20%20)
=![[FCH_{2}COO^{-}]](https://tex.z-dn.net/?f=%20%5BFCH_%7B2%7DCOO%5E%7B-%7D%5D%20%20)
= 0.00770 M
0.00257 x - 0.00001979 = 0.00005929
x = 0.031 M
Therefore, initial concentration of the weak acid is <u>0.031 M</u>
Parantheses mean present of a subgroup or a group of polyatomic ions in a chemical reaction.
<u>Explanation:</u>
In a chemical reaction, sometimes, a compound may be composed of group of polyatomic ions with other ions. Some of the polyatomic ions are sulfate, carbonate, nitrate, hydroxide, bicarbonate, ammonia etc.
So these polyatomic ions are formed by combining two or more elements. Thus, if the number of polyatomic ions in a compound is more than one, then we use parathesis and write those polyatomic ions in it and write the number of polyatomic ions present in the compound as subscript of the parathesis.
For example, Fe₂(SO₄)₃
So here SO₄ is a polyatomic ion and in the compound 3 atoms of SO₄ is required to neutralize the compound and thus paranthesis is used. Thus, parantheses mean present of a subgroup or a group of polyatomic ions in a chemical reaction.
Helium is a chemical element of the atomic number 2, an inert gas that is the lightest member of the noble gas series.
These means, Helium is lighter than air, and for this is why all other balloons may not float.
The helium balloon displaces an amount of air (Just like an empty water bottle displaces an amount of water). As long as the weight of the helium plus the balloon fabric is lighter than the air displaces, the balloon will float in the air.
Answer:
Below
Explanation:
Salt solution, aka saline solution, is a homogeneous mixture. This means that the mixtures composition is completely uniform throughout. If you were to look at a saline solution, it would just look like plain water because the salt is dissolved (it looks the exact same in the entire mixture).
Something like bean soup would be an example of a heterogeneous mixture. You can see all the beans and vegetables as components of one mixture.
Hope this helps! Best of luck <3
The answers from top to bottom right to left are
3,1,2,4
