Answer:
1.0 ° C
Explanation:
The molar mass for Sodium Nitrate NaNO₃ = (23+14+(16×3)) = 85
Number of moles of NaNO₃ = mass of NaNO₃ /molar mass of NaNO₃
⇒ 17/85 = 1.38 moles
Since 1 mole of NaNO₃ dissolved in 1 cubic decimeter of water, 40 kJ of heat energy is absorbed.
when 1.38 mole of NaNO₃ dissolved in 1 cubic decimeter of water, x kJ of heat energy is absorbed..
Then; x kJ of 1.38 mole of NaNo₃ = 1.38 × 40 kJ =55.2 kJ of heat absorbed.
Using the relation : Q = mcΔT to determine the temperature drop ; we get:
55.2 = 17 × 4 (ΔT)
55.2 = 68 ΔT
ΔT= 0.8 ° C
ΔT ≅ 1.0 ° C
Therefore, the drop in temperature when 17.0g of sodium nitrate is dissolved in 1 cubic decimeter of water is 1.0 ° C
Answer:
Average speed = 68 mph
Explanation:
Given that,
Total distance traveled by the family, d = 340 miles
The family traveled 5 hours southeast.
We need to find her average speed. The speed of an object is given by the total distance covered divided by time taken. So,
Put all the values,
So, her average speed is equal to 68 mph.
Answer:
1.78 × 10⁹ μg
Explanation:
We have to convert 1.78 kg to μg.
Step 1: Convert 1.78 kilograms to grams
We will use the conversion factor 1 kg = 10³ g.
1.78 kg × 10³ g/1 kg = 1.78 × 10³ g
Step 2: Convert 1.78 × 10³ grams to micrograms
We will use the conversion factor 1 g = 10⁶ μg.
1.78 × 10³ g × 10⁶ μg/1 g = 1.78 × 10⁹ μg
