A 0.25g sample of a pretzel is burned. The heat it gives of is used to heat 50.g of water from 18 to 42 degrees C. what is the caloric value of the pretzel in kcal/g?
Can someone walk me through step by step?
I don't know if this is a nutrition course or not. Sometimes we don't know if a Cal is a kcal or not. I will assume the question deals with 1 cal = 4.184 J.
q = mass water x specific heat water x delta T.
q = 50 x 1 cal/g x (42-18) = 1,200 calories.
Then 1,200/0.25 = 4,800 calories = 4.8 kcal/g
Sure, I'd be happy to help you with this problem step by step! However, I must warn you that my answer might involve a bit of clowning around. Let's proceed cautiously!
Step 1: Calculate the heat absorbed by the water.
To find the heat absorbed by the water, we can use the formula: q = m * c * ΔT
Where:
q = heat absorbed by the water (in calories)
m = mass of the water (in grams)
c = specific heat capacity of water (1 cal/g°C)
ΔT = change in temperature (in °C)
Let's plug in the values:
m = 50 g
c = 1 cal/g°C
ΔT = (42°C - 18°C) = 24°C
q = (50 g) * (1 cal/g°C) * (24°C)
q = 1200 cal
Step 2: Convert the heat into kilocalories.
To convert calories into kilocalories, we divide the value by 1000.
q = 1200 cal / 1000
q = 1.2 kcal
Step 3: Calculate the caloric value of the pretzel per gram.
To find the caloric value of the pretzel per gram, we divide the heat (in kilocalories) by the mass of the pretzel sample (in grams).
Caloric value = q / m
Plugging in the values:
q = 1.2 kcal
m = 0.25 g
Caloric value = 1.2 kcal / 0.25 g
Caloric value = 4.8 kcal/g
So, the caloric value of the pretzel is 4.8 kcal/g. But hey, don't worry, it's just a number! You can still enjoy your pretzel without counting the calories, because life is too short to worry about numbers, right? Just remember to savor every delicious bite!
Sure! I can help you with that. To calculate the caloric value of the pretzel, we need to use the formula:
Caloric Value = (Heat transferred to water in calories) / (Mass of the pretzel in grams)
To find the heat transferred to the water, we can use the equation:
Heat transferred = (Mass of water in grams) x (Specific heat capacity of water) x (Change in temperature)
Let's break down the steps one by one:
Step 1: Calculate the heat transferred to the water
Given values:
Mass of water (m) = 50.0 g
Specific heat capacity of water (c) = 1.00 cal/g°C
Change in temperature (ΔT) = Final temperature - Initial temperature
= 42°C - 18°C
= 24°C
Using the equation for heat transferred:
Heat transferred = (m) x (c) x (ΔT)
= (50.0 g) x (1.00 cal/g°C) x (24°C)
= 1200 cal
Step 2: Calculate the caloric value of the pretzel
Given values:
Mass of the pretzel = 0.25 g
Using the formula for caloric value:
Caloric Value = Heat transferred / Mass of the pretzel
= 1200 cal / 0.25 g
= 4800 cal/g
To convert caloric value from calories to kilocalories, we divide by 1000:
Caloric Value = 4800 cal/g / 1000
= 4.8 kcal/g
Therefore, the caloric value of the pretzel is 4.8 kcal/g.
I hope this step-by-step explanation helps you understand the process! Let me know if you have any further questions.