Answer:
Metal
Element: Calcium
Valency: 2
Explanation:
To find the element, let's use the periodic table. (Look below)
We already went past 3 shells, just need the 2 electrons after it.
Just skip to the 4th row and count 2 to the right
We end up at Calcium.
Calcium is a metal and we're also on the alkaline earth metals column.
Calcium will need to lose 2 electrons to reach stability, so the valency is 2.
The products will be magnesium phosphate and potassium chloride. You then have to watch a solubility chart to see which one of these is not soluable. In this case it is magnesium phosphate.
Answer:
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Explanation:
<u>1. Chemical balanced equation (given)</u>

<u>2. Mole ratio</u>

This is, 1 mol of NaOH will reacts with 1 mol of KHP.
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<u>3. Find the number of moles in 72.14 mL of the base</u>



<u>4. Find the number of grams of KHP that reacted</u>
The number of moles of KHP that reacted is equal to the number of moles of NaOH, 0.007055 mol
Convert moles to grams:
- mass = number moles × molar mass = 0.007055mol × 204.23g/mol
You have to round to 3 significant figures: 1.44 g (because the molarity is given with 3 significant figures).
<u>5. Find the percentage of KHP in the sample</u>
The percentage is how much of the substance is in 100 parts of the sample.
The formula is:
- % = (mass of substance / mass of sample) × 100
- % = (1.4408g/ 1.864g) × 100 = 77.3%
Chemical change creates a new substance
Answer:
Sodium hydroxide
Explanation:
Sodium hydroxide ( NaOH ) -
Sodium hydroxide is an inorganic compound , and is also called caustic soda and lye .
It is an ionic compound , which is white in color and is in solid state .
The cation and anion of this salt are the sodium cation Na⁺ and the hydroxide anions OH⁻ .
<u>It is highly basic in nature and is soluble in water , and when left open in air it can readily absorb moisture from the air , to form a hydrated sodium hydroxide .</u>