So, litmus paper is a qualitative tool for assessing the acidity or basicity of a substance (usually a solution). In general, blue litmus turns red in the presence of an acid, and red litmus turns blue in the presence of a base. They can't really tell you much more than that.
The solutions that are most likely acids are those that turn blue litmus red <em>and </em>do not evoke a color change in red litmus. A solution that turns red litmus blue <em>or </em>does not evoke a color change in blue litmus is likely not an acid. Using these criteria, solutions 4 and 7 are most likely acids since they both turn blue litmus red (and they cause no color change in red litmus).
The correct answer choice would thus be D.
The energy of an electron can be change only by set amounts.
The electrons in an energy level of an atom can only move to a higher or lower energy level only if it absorbs or emits a certain amount of energy. If the electron does not have enough energy to move to the next energy level then it will never move.
Answer:
gravity pull stuff down...
Explanation:
No. Although two such atoms are essentially chemically identical (they will chemically react in the same way), they are not completely identical.
The two solutions that have similar solubilities at 40°C will be Na₂HAsO₄ and Na₂SO₄.
<h3>
What is solubity ?</h3>
It is the ability of a solute to be dissolved, especially in water.
As the temperature increases the solubility of the gas generally decreases"
According to given information and graph attached as reference ;
- Solubility of NaCl (sodium chloride) at 40°C is 36.3 grams.
- Solubility of Na₂SO₄ (sodium sulfate) at 40°C is 48.8 grams.
- Solubility of Na₂HAsO₄ (sodium arsenate dibasic) at 40°C is 48.9
grams. - Solubility of Ba(NO₃)₂ (barium nitrate) at 40°C is 14.1 grams.
- Solubility of Ce₂(SO₄)₃·9H₂O (ceasium sulfate nonahydrate) at 40°C is 6.2 grams.
Lear more about solubility here ;
brainly.com/question/19221092
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