The correct answer is the one in the middle. Mixing food coloring and water
Answer:
Water splitting is the chemical reaction in which water is broken down into oxygen and hydrogen: 2 H2O → 2 H2 + O. Efficient and economical photochemical water splitting would be a technological breakthrough that could underpin a hydrogen economy.
Explanation: 2 H2O → 2 H2 + O.
Ionic compounds are those compounds which form an ion or
dissociates into ions when placed in a solution. These compounds are made up of
a metal and non metal. From the choices, here are the ionic compounds:
na2so4
h2so4
cacl2
<span>ca3(po4)2</span>
Answer:
She can add 380 g of salt to 1 L of hot water (75 °C) and stir until all the salt dissolves. Then, she can carefully cool the solution to room temperature.
Explanation:
A supersaturated solution contains more salt than it can normally hold at a given temperature.
A saturated solution at 25 °C contains 360 g of salt per litre, and water at 70 °C can hold more salt.
Yasmin can dissolve 380 g of salt in 1 L of water at 70 °C. Then she can carefully cool the solution to 25 °C, and she will have a supersaturated solution.
B and D are wrong. The most salt that will dissolve at 25 °C is 360 g. She will have a saturated solution.
C is wrong. Only 356 g of salt will dissolve at 5 °C, so that's what Yasmin will have in her solution at 25 °C. She will have a dilute solution.
Answer:
- NaClO₃ > KBr > KNO₃ > NaCl.
Explanation:
The attached file contains the graph with the solubility curves for the four substances, KNO₃, NaClO₃, KBr, NaCl.
To determine the solubility of each salt at a certain temperature, you read the temperature on the horizontal axis, labeled Temperature (ºC), and move upward up to intersecting the curve of the corresponding salt. Then, move horizontally up to insersceting the vertical axis, labeled Solubility (g/100g of H₂O), to read the solubility.
The higher the reading on the vertical axis, the higher the solubility.
The red vertical line that I added is at a temperature of 40ºC.
The number in blue indicate the order in which the solubility curves are intersected at that temperature:
- 4: NaCl: this is the lowest solubility
- 3: KNO₃: this is the second lowest solubility
- 2: KBr: this is the third lowest solubility
- 1: NaClO₃: this is the highest solubility.
Thus, the rank, from most soluble to least soluble is:
- NaClO₃ > KBr > KNO₃ > NaCl.
