#6). Every 1,000 mL makes 1 L How many 1,000mL are there in 2,800 mL ? That's division. (2,800 mL) / (1,000 mL) = <em>2.8 L</em>
#7). The 'perimeter' means the 'distance all the way around'. You have to know that both sides of a rectangle are the same length, and also the top and bottom are the same length. So the perimeter of this rectangle is
(2 yd) + (4.5 yd) + (2.yd) + (4.5 yd) = 13 yd .
Oops. The problem wants to know the perimeter in feet. So you have to know that each yard is the same as 3 feet. In order to find the number of feet in 13 yards, you have to take 3 feet 13 <em><u>times</u></em> .
(3 feet) times (13) = <em>39 feet .</em>
#8). For this one, you have to know that every 36 inches makes 1 yard.
How many 36 inches are there in 48 inches ? That's division. (48 inches) / (36inches) = <em>1 and 1/2 yards</em> .
#9). For this problem, you have to know how to handle a mixed number, and you also have to know that there are 16 ounces in 1 pound.
Now, remember that each pound is the same as 16 ounces. So if you want to find the number of ounces in 9-1/2 pounds, you have to take 16 ounces 9-1/2 times .
(16 ounces) times (9-1/2) = <em>152 ounces</em>. ___________________________________
#10). This one is just adding up some numbers. But after you finish doing that, you have to know that 1,000 meters is called '1 kilometer' .
Students have investigated what's going on in the fictional town of Westfield, they learned that the mysterious reddish-brown substance in the water is actually rust, which formed because of a chemical reaction between the iron pipes and the fertilizer substance in the water.
Given the solubility of strontium arsenate is 0.0480 g/l . we have to convert it into mol/L by dividing it over molar mass (540.7 g/mol) Molar solubility = 0.0480 / 540.7 = 8.9 x 10⁻⁵ mol/L Dissociation equation: Sr₃(AsO₄)₂(s) → 3 Sr²⁺(aq) + 2 AsO₄³⁻(aq) 3 s 2 s Ksp = [Sr²⁺]³ [AsO₄³⁻]² = (3s)³ (2s)² = 108 s⁵ Ksp = 108 (8.9 x 10⁻⁵) = 5.95 x 10⁻¹⁹