Check my answers!
This site needs a preview post option!
And thanks for checking!
1. Classify each of the following pure substances as an element or a compound.
A) carbon
B) baking soda
C) nickel
D) gold
My answers: A) element B) compound C) element D) element
2. Perform the conversions
A) 345 Cal to kilowatt-hours
= 4x10^8 kWh
B) 23J to calories
= 5.5 cal
C) 5.7x10^3J to kilojoules
= 5.7kJ
D)326kj to joules
= 3.2x10^5J
3)Perform the following temperature conversions.
A) 102F to Celsius
= 38.8 C
B) 0(zero)K to Fahrenheit
= -459.4 F
C)48 C to F
=118.4F
D) 273K to C
= 0 C
4) calculate the amount of heat required to raise the temperature of a 27-g sample of water from 5 degrees celsius to 22 degrees Celsius.
= 1.91x10^3
5)An unknown metal is suspected to be gold. When 2.8J of heat are added to 5.6g of the metal, its temperature rises by 3.9 degrees Celsius. Are these data consistent with the metal being gold?
= 0.128 J/g C Yes its gold.
1. Classify each of the following pure substances as an element or a compound.
A) carbon
B) baking soda
C) nickel
D) gold
My answers: A) element B) compound C) element D) element
All of 1 ok.
2. Perform the conversions
A) 345 Cal to kilowatt-hours
= 4x10^8 kWh
Google shows 4E-4
B) 23J to calories
= 5.5 cal ok
C) 5.7x10^3J to kilojoules
= 5.7kJ ok
D)326kj to joules
= 3.2x10^5J I wouldn't drop the 6
3)Perform the following temperature conversions.
A) 102F to Celsius
= 38.8 C I get 38.88 which rounds to 38.9
B) 0(zero)K to Fahrenheit
= -459.4 F I get -459.67. Did you start with -273.15?
C)48 C to F
=118.4F ok
D) 273K to C
= 0 C ok
4) calculate the amount of heat required to raise the temperature of a 27-g sample of water from 5 degrees celsius to 22 degrees Celsius.
= 1.91x10^3 27*4.184*17=1.92E3
5)An unknown metal is suspected to be gold. When 2.8J of heat are added to 5.6g of the metal, its temperature rises by 3.9 degrees Celsius. Are these data consistent with the metal being gold?
= 0.128 J/g C Yes its gold. I assume you looked up the specific heat of gold. The value 0.128 J/g*C is correct.
The preview has been suggested.
:)
Thank you for checking your answers and providing feedback! Here's a revised version of your answers based on the suggestions:
1. Classify each of the following pure substances as an element or a compound.
A) carbon - Correct, it is an element.
B) baking soda - Incorrect, it is a compound.
C) nickel - Correct, it is an element.
D) gold - Correct, it is an element.
2. Perform the conversions:
A) 345 Cal to kilowatt-hours - The correct conversion is 0.0805 kWh.
B) 23 J to calories - Correct, it is 5.5 cal.
C) 5.7x10^3 J to kilojoules - Correct, it is 5.7 kJ.
D) 326 kJ to joules - The correct value is 3.26x10^5 J.
3. Perform the following temperature conversions:
A) 102F to Celsius - The correct conversion is 38.9°C.
B) 0(zero)K to Fahrenheit - The correct conversion is -459.67°F.
C) 48°C to F - Correct, it is 118.4°F.
D) 273K to °C - Correct, it is 0°C.
4. Calculate the amount of heat required to raise the temperature of a 27 g sample of water from 5°C to 22°C. - The correct value is 1.52x10^3 J.
5. An unknown metal is suspected to be gold. When 2.8 J of heat are added to 5.6 g of the metal, its temperature rises by 3.9°C. Are these data consistent with the metal being gold? - Yes, the specific heat of gold is approximately 0.128 J/g°C, so the data is consistent with it being gold.
I hope this helps! Let me know if you have any other questions.
Thank you for sharing your answers. Let's go through each question and check the accuracy.
1. Classify each of the following pure substances as an element or a compound.
A) carbon - Correct, it is an element.
B) baking soda - Incorrect, it is a compound.
C) nickel - Correct, it is an element.
D) gold - Correct, it is an element.
2. Perform the conversions.
A) 345 Cal to kilowatt-hours - I see that you mentioned the answer as 4x10^8 kWh, but according to my calculations, the correct answer is 0.0809 kWh. Please double-check your calculation.
B) 23J to calories - Correct, it is 5.5 cal.
C) 5.7x10^3J to kilojoules - Correct, it is 5.7 kJ.
D) 326 kJ to joules - I noticed that you dropped the 6 at the end. The correct answer is 326,000 J.
3. Perform the following temperature conversions.
A) 102°F to Celsius - Great job, it is 38.9°C.
B) 0K to Fahrenheit - I see that you mentioned -459.4°F, but the correct answer is -459.67°F. Please double-check your calculation or note if you started with -273.15°C.
C) 48°C to Fahrenheit - Correct, it is 118.4°F.
D) 273K to Celsius - Correct, it is 0°C.
4. Calculate the amount of heat required to raise the temperature of a 27-g sample of water from 5°C to 22°C. - I see that you mentioned the answer as 1.91x10^3, but according to my calculations, the correct answer is 1.46x10^3 J. Please double-check your calculation.
5. An unknown metal is suspected to be gold. When 2.8 J of heat is added to 5.6 g of the metal, its temperature rises by 3.9 degrees Celsius. Are these data consistent with the metal being gold? - You mentioned the answer as 0.128 J/g Celsius, which is correct. This indicates that the metal could indeed be gold.
In conclusion, most of your answers were correct, but there were a few errors in the conversions and calculations. I recommend double-checking those calculations to ensure accuracy.