1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
antiseptic1488 [7]
3 years ago
5

#1: Which of the following is the abbreviation for a unit of energy? A. K / B. °C/ C. W / D. cal............... #2: A 200 g bloc

k of a substance requires 1.84 kJ of heat to raise its temperature from 25°C to 45°C. Use the table attached to identify the substance. A. iron/ B. aluminum/ C. gold/ D. copper.....................#3: In a calorimeter, the temperature of 100 g of water decreased by 10°C when 10 g of ice melted. How much heat was absorbed by the ice? A. 418 kJ / B. 100 kJ / C. 10 J / D. 4.18 kJ ..................#4: The amount of heat needed to raise the temperature of 50 g of a substance by 15°C is 1.83 kJ. What is the specific heat of the substance? A. 2.44 J/g-°C / B. 2.22 J/g-°C / C. 2.13 J/g-°C / D. 2.05 J/g-°C ................#5: In a calorimeter, 3.34 kJ of heat was absorbed when 10 g of ice melted. What is the enthalpy of fusion of the ice? A. 6.68 J/g / B. 334 J/g / C. 6.68 kJ/g/ D. 334 kJ/g
Chemistry
2 answers:
stealth61 [152]3 years ago
8 0
Among the choices, the unit of energy is calories. Answer in 1) is D. In 2) we are given with te mass , heat and temperature change. we just need to get the heat capacity and compare it with the following metals. The calculated heat capacity is 0.46 kJ/kg K. The answer is A. iron. In 3) we can compute the heat absorbed by the formula ΔH=mCpΔT. Cp of water is 4.18 J/g K. Answer of 3) is D. In 4) the formula used in Cp=ΔH/mΔT. Answer in 4) is A. The heat of enthalpy of fusion of ice is 80 cal/g. We convert this to J/g. Answer  in 5) is B.334 J/g.
Ivenika [448]3 years ago
7 0

Answer:

1. D. cal......

2.A. iron

3. D

4.2.44j/g°C   A

5,Lf=334J/g   B

Explanation:

1: Which of the following is the abbreviation for a unit of energy? A. K / B. °C/ C. W / D. cal...............

calorie is the unit of energy

#2: A 200 g block of a substance requires 1.84 kJ of heat to raise its temperature from 25°C to 45°C. Use the table attached to identify the substance. A. iron/ B. aluminum/ C. gold/ D. copper.....................

Q=mcdt

1840=0.2*C*(45-25)

C=460J/KgK

if the specific heat capacity is the above then he substance is iron

#3: In a calorimeter, the temperature of 100 g of water decreased by 10°C when 10 g of ice melted. How much heat was absorbed by the ice? A. 418 kJ / B. 100 kJ / C. 10 J / D. 4.18 kJ .................

Q=mcdT

Q=0.1*10*4180

Q=4180j. answer D

.#4: The amount of heat needed to raise the temperature of 50 g of a substance by 15°C is 1.83 kJ. What is the specific heat of the substance? A. 2.44 J/g-°C / B. 2.22 J/g-°C / C. 2.13 J/g-°C / D. 2.05 J/g-°C ................

Q=mcdT

1830=50/1000*C*15

C=2440j/kg/k

change it to j/g°C

2.44j/g°C   A

#5: In a calorimeter, 3.34 kJ of heat was absorbed when 10 g of ice melted. What is the enthalpy of fusion of the ice? A. 6.68 J/g / B. 334 J/g / C. 6.68 kJ/g/ D. 334 kJ/g

Q=mLf

Lf=enthalpy of fusion

3340/10=Lf

Lf=334J/g   B

Enthalpy of fusion quantity of heat to convert 1 unit mass of a solid to liquid without any noticeable change in temperature.

You might be interested in
If 5.0 moles of C3H8 react, how many molecules of water are formed?
artcher [175]
Balance Chemical Equation for combustion of Propane is as follow,

                         C₃H₈  +  5 O₂    →    3 CO₂  +  4 H₂O

According to equation,

              1 mole of C₃H₈ on combustion gives  =  4 moles of H₂O
So,
        5 moles of C₃H₈ on combustion will give  =  X moles of H₂O

Solving for X,
                                    X  =  (5 mol × 4 mol) ÷ 1 mole

                                    X  =  20 moles of H₂O

Calculating number of molecules for 20 moles of H₂O,
As,
                        1 mole of H₂O contains  =  6.022 × 10²³ molecules
So,
                20 moles of H₂O will contain  =  X molecules

Solving for X,
                                 X  =  (20 mole × 6.022 × 10²³ molecules) ÷ 1 mol

                                 X  =  1.20 ×10²⁵ Molecules of H₂O
8 0
3 years ago
Iodine 131, cesium 137, and strontium 90 are all considered isotopes. What are isotopes?
Nitella [24]

Answer:

Isotopes are variants of an element, where the number of neutrons is different but its number of protons stay the same.

Explanation:

If the number of protons had changed then it would just be a different element.

Electron number changing simply adds charge to the atom, and doesn't change it or anything.

PLS GIVE BRAINLIEST

3 0
2 years ago
Read 2 more answers
Under what conditions does the molar volume of a gas decrease
nydimaria [60]

Answer:

Gases are compressible, meaning that when put under high pressure, the particles are forced closer to one another. This decreases the amount of empty space and reduces the volume of the gas. Gas volume is also affected by temperature. When a gas is heated, its molecules move faster and the gas expands.

4 0
2 years ago
Read 2 more answers
chegg write a net ionic equation describing the oxidation of no2 2 to no3 2 by o2 in a basic solution.
Marina86 [1]

When the same species undergoes both oxidation and reduction in a single redox reaction, this is referred to as a disproportionation. Therefore, divide it into two equal reactions.

NO2→NO^−3

NO2→NO

and do the usual changes

First, balance the two half reactions:

3. NO2 +H2O →NO^−3 + 2 H^+ + e−

4. NO2 +2 H^+ + 2e− → NO + H2O

Now multiply one or both half-reactions to ensure that each has the same number of electrons. Here, Eqn (3) x 2 results in each half-reaction having two electrons:

5. 2 NO2 + 2 H2O → 2 NO^−3 + 4H^+ + 2e−

Now add Eqn 4 and 5 (the electrons now cancel each other):

3NO2 + 2H^+ + 2H2O → NO + 2 NO−3 + H2O + 4H+

and cancel terms that’s common to both sides:

3NO2 + H2O → NO + 2NO^−3 + 2H+

This is the net ionic equation describing the oxidation of NO2 to NO3 in basic solution.

Learn more about balancing equation here:

brainly.com/question/26227625

#SPJ4

7 0
1 year ago
What do scientists make to help them make a hypothesis or collect data during an experiment
Veronika [31]
They will most likely make a table, or some sort of graphing chart
5 0
3 years ago
Other questions:
  • A hotdog is matter, but the heat that cooks it is?
    10·1 answer
  • Arrange the elements given below in the increasing order of their atomic size. Element A 1s22s22p6 
Element B 1s22s2
 Element C
    9·1 answer
  • It usually takes Vaughn 12 minutes to drive to school. She drives an average of 50.0 miles per hour. What is the distance from s
    5·1 answer
  • In the enzyme reaction above, catechol is the substrate, oxygen is a reactant, catechol oxidase is the enzyme, benzoquinone is t
    10·1 answer
  • thank you so much for helping me I don't know science that well trying to get better I've been getting better good grades but st
    13·1 answer
  • Check all items common to bases:
    12·2 answers
  • Use the data, the periodic table, and the station resources to complete the data table and answer the questions below.
    8·1 answer
  • Anyone know the answer to this one?
    15·1 answer
  • HELPPPPP ASAP PLEASEEE
    8·2 answers
  • Importancia de la química orgánica en el desarrollo de los seres vivos.
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!