Answer:
D. It is a chemical reaction because the total mass remains the same when new substances are formed.
Explanation:
A chemical reaction is represented by a chemical equation which show the reactant and products. Reactants are written on left side of arrow while products are written on right side. The number of atoms are remain same however arrangement of atoms is different on both side.
For example:
6H₂O + 6CO₂ + energy → C₆H₁₂O₆ + 6O₂
it is known from balanced chemical equation that 6 moles of carbon dioxide react with the six moles of water and created one mole of glucose and six mole of oxygen. The number of atoms are same on both side however arrangement of atoms is different.
While in case of nuclear reaction small change in mass take place.
Answer: The concentration of 
ions in vinegar is 0.001 M.
Explanation:
Given: pH = 3.0
pH is the negative logarithm of concentration of hydrogen ion.
The expression for pH is as follows.
![pH = - log [H^{+}]](https://tex.z-dn.net/?f=pH%20%3D%20-%20log%20%5BH%5E%7B%2B%7D%5D)
Substitute the value into above expression as follows.
![pH = - log [H^{+}]\\3.0 = - log [H^{+}]\\conc. of H^{+} = antilog (- 3.0)\\= 0.001 M](https://tex.z-dn.net/?f=pH%20%3D%20-%20log%20%5BH%5E%7B%2B%7D%5D%5C%5C3.0%20%3D%20-%20log%20%5BH%5E%7B%2B%7D%5D%5C%5Cconc.%20of%20H%5E%7B%2B%7D%20%3D%20antilog%20%28-%203.0%29%5C%5C%3D%200.001%20M)
Thus, we can conclude that the concentration of ions in vinegar is 0.001 M.
he required empirical formula based on the data provided is Na2CO3.H2O.
<h3>What is empirical formula?</h3>
The term empirical formula refers to the formula of a compound which shows the ratio of each specie present.
We have the following;
Mass of sodium = 37.07-g
Mass of carbonate = 48.39 g
Mass of water = 14.54-g
Number of moles of sodium = 37.07-g/23 g/mol = 2 moles
Number of moles of carbonate = 48.39 g/61 g/mol = 1 mole
Number of moles of water = 14.54/18 g/mol = 1 mole
The mole ratio is 2 : 1: 1
Hence, the required empirical formula is Na2CO3.H2O
Learn more about empirical formula : brainly.com/question/11588623
1. Solids
- definite volume & shape
- little energy
-vibrate in place
- very incompressible
2. Liquids
- held together yet can still flow
Noble gases have complete valence electron shells
