Answer:
D. chemical alters the atomic structure of a substance, while physical does not
hope this helps!
Answer:
La densidad experimenta una disminución
Explanation:
Hola!
En este caso, debemos recordar que la adición de agua incrementa el volumen donde se encuentra un soluto disuelto, el cual posee una cantidad de materia constante. De este modo, sabiendo que la densidad es:

Al incrementar el denominador (volumen), la densidad experimenta una disminución, al estar en relación inversamente proporcional.
Muchos saludos!
I think the answer is a molecule
Answer:
The pH is 9,21.
Explanation:
The pH indicates the acidity or basicity of a substance. PH values between 0 and less than 7 indicate acidic solutions, 7 neutral and higher than 7 to 14 basic. It is calculated as
pH = -log (H 30+)
pH= -log (6,2 x 10^-10)
<em>pH=9,21</em>
Answer:
0.10M HCN < 0.10 M HClO < 0.10 M HNO₂ < 0.10 M HNO₃
Explanation:
We are comparing acids with the same concentration. So what we have to do first is to determine if we have any strong acid and for the rest ( weak acids ) compare them by their Ka´s ( look for them in reference tables ) since we know the larger the Ka, the more Hydronium concentration will be in these solutions at the same concentration.
HNO₃ is a strong acid and will have the largest hydronium concentration.
HCN Ka = 6.2 x 10⁻¹⁰
HNO₂ Ka = 4.0 x 10⁻⁴
HClO Ka = 3.0 x 10⁻⁸
The ranking from smallest to largest hydronium concentration will then be:
0.10M HCN < 0.10 M HClO < 0.10 M HNO₂ < 0.10 M HNO₃