Answer:
B) exothermic.
Explanation:
Hello!
In this case, we need to keep in mind that exothermic reactions release heat, so they increase the temperature as the final energy is less than the initial energy; in contrast, endothermic reactions absorb heat, so they decrease the temperature as the final energy is greater than the initial energy.
In such a way, when a dissolution process shows off a negative enthalpy of dissolution, we infer it is an exothermic process due to the aforementioned; therefore, the answer is:
B) exothermic .
Best regards!
What is the nickname for mitochondria
Answer:
the powerhouse of the cell
An irregularly-shaped piece of aluminum (Al) has a mass of 66.0 grams. What is the volume in cm³ of this piece of aluminum if its density is 2.70 g/cm³?
Answer:
[tex]V=24.45\ \text{cm}^3[/tex]
Explanation:
Given that,
Mass of a piece of Aluminium, m = 66 grams
The density of Aluminium, d = 2.70 g/cm³
We need to find the volume of this piece in cm³.
We know that,
Density = mass per unit volume
[tex]d=\dfrac{m}{V}\\\\V=\dfrac{m}{d}\\\\V=\dfrac{66\ g}{2.7\ g/cm^3}\\\\V=24.45\ \text{cm}^3[/tex]
So, the volume of the piece is [tex]24.45\ \text{cm}^3[/tex].
The flask contains 10.0 mL of HCl and a few drops of phenolphthalein indicator. The buret contains 0.150 M NaOH. It requires 21.4 mL of the NaOH solution to reach the end point of the titration. A buret filled with a titrant is held above a graduated cylinder containing an analyte solution. What is the initial concentration of HCl
Answer:
0.321 M
Explanation:
The neutralization reaction of HCl with NaOH is the following:
HCl(aq) + NaOH(aq) → NaCl(aq) + H₂O(l)
So, 1 equivalent of HCl reacts with 1 equivalent of NaOH. In this case:
1 equivalent HCl = 1 mol HCl
1 equivalent NaOH = 1 mol NaOH
At the equivalence point, the amount of HCl reacts completely with the added amount of titrant (NaOH). As 1 mol of reactant is calculated from the product of the molarity of the solution and the volume, in the equivalent point:
moles HCl = moles NaOH
M(HCl) x V(HCl) = M(NaOH) x V(NaOH)
We have:
M(NaOH) = 0.150 M
V(NaOH) = 21.4 mL = 0.0214 L
V(HCl) = 10.0 mL = 0.01 L
Thus, we calculate the initial concentration HCl as follows:
M(HCl) = (M(NaOH) x V(NaOH))/ (V(HCl))
= (0.150 M x 0.0214 L)/(0.01 L) = 0.321 M
What were the two main reasons that Dmitri Mendeleev's periodic table was more successful than Lothar Meyer's?
Answer:
it helped alot of dcientisd
Explanation:
Answer:
Next, Mendeleev began a text for inorganic chemistry (concerned with substances that are not organic, such as minerals), and the result, Principles__of Chemistry (two volumes, 1868–1870), would become the standard text for the field until early in the 20th century. His research for this book would also lead him to his most renowned work.
Explanation:
reddit mcat In a titration, 27.4 mL of a 0.0154 M solution of Ba(OH)2 is needed to neutralize 20.0 mL of HCl. What was the concentration of the acid solution
Answer:
0.422 M
Explanation:
Equation of the reaction,
2HCl(aq) + Ba(OH)₂(aq) ⇒ BaCl₂(aq)+2H₂O(l)
From the recation above,
2 moles of HCl is needed to neutralize 1 mole of Ba(OH)₂.
Using,
C'V'/CV = a/b......................... Equation 1
Where C' = concentration of acid, C = concentration of base, V' = volume of acid, V = volume of base, a = number of moles of acid, b = number of moles of base.
make C' the subject of the equation.
C' = aCV/bV'................. Equation 2
a = 2 mole, b = 1 mole, C = 0.0154 M, V = 27.4 mL, V' = 20 mL
Substitute into equation 2
C' = (2×0.0154×27.4)/(1×20)
C' = 0.422 M.
Hence the concentration of acid is 0.422 M
An ion can be created when a .................... is lost or gained by an element.
Answer:
electron and ignore this woejdnks
Write the balanced COMPLETE ionic equation for the reaction when aluminum nitrate and sodium hydroxide are mixed in aqueous solution. If no reaction occurs, simply write only NR.
Answer:See explanation
Explanation:
MOLECULAR REACTION EQUATION;
Al(NO3)3(aq) + 3NaOH(aq) --->Al(OH)3(s) +3NaNO3(aq)
complete ionic equation:
Al^3+(aq) + 3NO3^-(aq) + 3Na^+(aq) + 3OH^-(aq) ---->Al(OH)3(s) + 3Na^+(aq) + 3NO3^-(aq)
Net ionic reaction equation;
Al^3+(aq) + 3OH^-(aq) ------> Al(OH)3(s)
how many moles of H2O are needed to react with a mole of 3.0 of Na?
Answer: 3.0 moles of water [tex](H_2O)[/tex] are needed to react with a mole of 3.0 of Na
Explanation:
The balanced chemical reaction of sodium with water is as follows:
[tex]2Na+2H_2O\rightarrow 2NaOH+H_2[/tex]
According to stoichiometry:
2 moles of sodium [tex](Na)[/tex] reacts with = 2 moles of water [tex](H_2O)[/tex]
Thus 3.0 moles of sodium [tex](Na)[/tex] reacts with = [tex]\frac{2}{2}\times 3.0=3.0[/tex] moles of water [tex](H_2O)[/tex]
3.0 moles of water [tex](H_2O)[/tex] are needed to react with a mole of 3.0 of Na
Does acid rain make new substances? Construct an argument that uses data from this investigation as evidence for your claim.
Answer:
Acid rain, like all acids, generates dissolution of chemical compounds, and reacts together with bases to be able to carry out oxide reduction reactions, which by deduction is very likely to form new substances as a result of the dissolution or acid erosion caused.
Explanation:
Acid rain is more likely to occur in large cities or large sources of pollution, since the excess of carbon dioxide in the atmosphere causes it to increase its partial pressure in a condensed way in the clouds, this is how then this cloud when being loaded with water and then generating the rain drags these masses of condensed carbon dioxide in the form of acid rain.
The degree of acidity is directly proportional to the amount of partial pressure of carbon dioxide in the atmosphere.
A student is making a glucose solution. The student is using 12.55 g of glucose (C6H1206) and a 500 mL volumetric flask. Use this information to calculate the molarity of the glucose solution.
Answer:
M = 0.138 M
Explanation:
Given data:
Mass of glucose = 12.55 g
Volume of solution = 500 mL
Molarity of solution = ?
Solution:
Molarity is used to describe the concentration of solution. It tells how many moles are dissolve in per litter of solution.
Formula:
Molarity = number of moles of solute / L of solution
Number of moles of glucose:
Number of moles = mass/molar mass
Number of moles = 12.55 g/ 180.156 g/mol
Number of moles = 0.069 mol
Volume in L:
500 mL × 1 L /1000 mL
0.5 L
Molarity:
M = 0.069 mol / 0.5 L
M = 0.138 M
P4010
+ 4P + 5 O2
How many moles of phosphorus would be
produced if 8.19 mol of P4010 reacted? Enter
your answer with 2 decimal places.
Answer:
32.76mole of P
Explanation:
The reaction expression is given as;
P₄O₁₀ → 4P + 5O₂
Given parameters:
Number of moles of P₄O₁₀ = 8.19mol
Unknown:
Number of moles of P produced = ?
Solution:
From the balanced reaction expression;
1 mole of P₄O₁₀ will produce 4 mole of P
8.19mole of P₄O₁₀ will therefore produce 4 x 8.19 = 32.76mole of P
Can anybody answer this question of chemistry?
Answer:
Answer:A
Answer:AExplanation:
Answer:AExplanation:Molar Mass of glucose = (6×12)+(1×12)+(16×6)= 180g/mol
= 180g/molNumber of moles of Glucose = Mass/Molar Mass
= 180g/molNumber of moles of Glucose = Mass/Molar Mass= 5000/180
= 180g/molNumber of moles of Glucose = Mass/Molar Mass= 5000/180= 27.7778moles
= 180g/molNumber of moles of Glucose = Mass/Molar Mass= 5000/180= 27.7778molesIn the balanced equation of fermentation, the ratio of glucose to ethanol is 2:1
= 180g/molNumber of moles of Glucose = Mass/Molar Mass= 5000/180= 27.7778molesIn the balanced equation of fermentation, the ratio of glucose to ethanol is 2:1Therefore the number of moles of ethanol is 2×27.7778
= 180g/molNumber of moles of Glucose = Mass/Molar Mass= 5000/180= 27.7778molesIn the balanced equation of fermentation, the ratio of glucose to ethanol is 2:1Therefore the number of moles of ethanol is 2×27.7778=55.5556moles
= 180g/molNumber of moles of Glucose = Mass/Molar Mass= 5000/180= 27.7778molesIn the balanced equation of fermentation, the ratio of glucose to ethanol is 2:1Therefore the number of moles of ethanol is 2×27.7778=55.5556molesMass of ethanol= Molar Mass of ethanol × Number of moles
= 180g/molNumber of moles of Glucose = Mass/Molar Mass= 5000/180= 27.7778molesIn the balanced equation of fermentation, the ratio of glucose to ethanol is 2:1Therefore the number of moles of ethanol is 2×27.7778=55.5556molesMass of ethanol= Molar Mass of ethanol × Number of moles={(12×2)+(1×6)+16} × 55.5556
= 180g/molNumber of moles of Glucose = Mass/Molar Mass= 5000/180= 27.7778molesIn the balanced equation of fermentation, the ratio of glucose to ethanol is 2:1Therefore the number of moles of ethanol is 2×27.7778=55.5556molesMass of ethanol= Molar Mass of ethanol × Number of moles={(12×2)+(1×6)+16} × 55.5556= 46.5×55.5556
= 180g/molNumber of moles of Glucose = Mass/Molar Mass= 5000/180= 27.7778molesIn the balanced equation of fermentation, the ratio of glucose to ethanol is 2:1Therefore the number of moles of ethanol is 2×27.7778=55.5556molesMass of ethanol= Molar Mass of ethanol × Number of moles={(12×2)+(1×6)+16} × 55.5556= 46.5×55.5556= 2555.55
Answer:
Answer:A
Answer:AExplanation:
Answer:AExplanation:Molar Mass of glucose = (6×12)+(1×12)+(16×6)= 180g/mol
= 180g/molNumber of moles of Glucose = Mass/Molar Mass
= 180g/molNumber of moles of Glucose = Mass/Molar Mass= 5000/180
= 180g/molNumber of moles of Glucose = Mass/Molar Mass= 5000/180= 27.7778moles
= 180g/molNumber of moles of Glucose = Mass/Molar Mass= 5000/180= 27.7778molesIn the balanced equation of fermentation, the ratio of glucose to ethanol is 2:1
= 180g/molNumber of moles of Glucose = Mass/Molar Mass= 5000/180= 27.7778molesIn the balanced equation of fermentation, the ratio of glucose to ethanol is 2:1Therefore the number of moles of ethanol is 2×27.7778
= 180g/molNumber of moles of Glucose = Mass/Molar Mass= 5000/180= 27.7778molesIn the balanced equation of fermentation, the ratio of glucose to ethanol is 2:1Therefore the number of moles of ethanol is 2×27.7778=55.5556moles
= 180g/molNumber of moles of Glucose = Mass/Molar Mass= 5000/180= 27.7778molesIn the balanced equation of fermentation, the ratio of glucose to ethanol is 2:1Therefore the number of moles of ethanol is 2×27.7778=55.5556molesMass of ethanol= Molar Mass of ethanol × Number of moles
= 180g/molNumber of moles of Glucose = Mass/Molar Mass= 5000/180= 27.7778molesIn the balanced equation of fermentation, the ratio of glucose to ethanol is 2:1Therefore the number of moles of ethanol is 2×27.7778=55.5556molesMass of ethanol= Molar Mass of ethanol × Number of moles={(12×2)+(1×6)+16} × 55.5556
= 180g/molNumber of moles of Glucose = Mass/Molar Mass= 5000/180= 27.7778molesIn the balanced equation of fermentation, the ratio of glucose to ethanol is 2:1Therefore the number of moles of ethanol is 2×27.7778=55.5556molesMass of ethanol= Molar Mass of ethanol × Number of moles={(12×2)+(1×6)+16} × 55.5556= 46.5×55.5556
= 180g/molNumber of moles of Glucose = Mass/Molar Mass= 5000/180= 27.7778molesIn the balanced equation of fermentation, the ratio of glucose to ethanol is 2:1Therefore the number of moles of ethanol is 2×27.7778=55.5556molesMass of ethanol= Molar Mass of ethanol × Number of moles={(12×2)+(1×6)+16} × 55.5556= 46.5×55.5556= 2555.55
if you know an object's distance from the sun in kilometers,how can you find the distance in AU?
Answer:
We divide our value by 1.5×10⁸
Explanation:
AU is a unit to determine distance in the space.
We know that AU means astronomic unit.
The value for conversion is 1.5×10⁸ Km
1 AU = 1.5×10⁸ Km
Let's see the example:
One star is located from the sun, around 3.35×10¹⁰ Km away. To determine the distance in AU we use the conversion factor:
3.35×10¹⁰ Km . 1 AU / 1.5×10⁸ Km = 223.3 AU
Calculate the molar mass of hafnium (II) iodide, HfI2. This is 1 Hf and 2 Iodine. No hydrogen.
When C2H4(g) reacts with H2O(g) to form CH3CH2OH(g) according to the following equation, energy is released into the surroundings. C2H4(g) H2O(g) CH3CH2OH(g) Is this reaction endothermic or exothermic
Answer:
Exothermic
General Formulas and Concepts:
Chemistry
Thermodynamics
Exothermic - releases heat as a productEndothermic - absorbs heat as a reactantExplanation:
We are given that the reaction takes place between C₂H₄ (g) and H₂O (g) to form CH₃CH₂OH (g) and is releasing heat.
This means that heat would be product as it is being released during the reaction.
Therefore, we have an exothermic reaction.
A scientist measures the standard enthalpy change for the following reaction to be -17.2 kJ : Ca(OH)2(aq) 2 HCl(aq)CaCl2(s)
2 H2O(l) Based on this value and the standard enthalpies of formation for the other substances, the standard enthalpy of formation of HCl(aq) is kJ/mol.
Answer: [tex]\Delta H^{0}=-173.72[/tex] kJ/mol
Explanation: Enthalpy Change is the amount of energy in a reaction - absorption or release - at a constant pressure. So, Standard Enthalpy of Formation is how much energy is necessary to form a substance.
The standard enthalpy of formation of HCl is calculated as:
[tex]\Delta ^{0}=\Sigma H_{products}-\Sigma H_{reactants}[/tex]
[tex]Ca(OH)_{2}_{(aq)}+2HCl_{(aq)}[/tex] → [tex]CaCl_{2}_{(s)}+2H_{2}O_{(l)}[/tex]
Standard Enthalpy of formation for the other compounds are:
Calcium Hydroxide: [tex]\Delta H^{0}=[/tex] -1002.82 kJ/mol
Calcium chloride: [tex]\Delta H^{0}=[/tex] -795.8 kJ/mol
Water: [tex]\Delta H^{0}=[/tex] -285.83 kJ/mol
Enthalpy is given per mol, which means we have to multiply by the mols in the balanced equation.
Calculating:
[tex]-17.2=[-795.8+2(285.85)]-[-1002.82+2\Delta H][/tex]
[tex]-17.2=-1367.46+1002.82-2\Delta H[/tex]
[tex]2\Delta H=17.2-364.64[/tex]
[tex]\Delta H=-173.72[/tex]
So, the standard enthalpy of formation of HCl is -173.72 kJ/mol
what is the molarity of a solutoin which contains 38.5 g of sodium chloride disolved in 325 ml solution ?
Answer:
Molarity = 2.02 M
Explanation:
Given data:
Molarity of solution = ?
Mass of sodium chloride = 38.5 g
Volume of solution = 325 mL (0.325 L)
Solution:
Number of moles = mass/molar mass
Number of moles = 38.5 g/ 58.44 g/mol
Number of moles = 0.658 mol
Molarity:
Molarity = number of moles / volume of solution in L
Molarity = 0.658 mol /0.325 L
Molarity = 2.02 M
Why do earthquakes occur more often in some countries than in others?
Answer:
Some places have more earthquakes than others because they sit on the edges of tectonic plates.
Mercury, also known as quicksilver, is a metallic element and a liquid at room temperature. Calculate mercury's density if a sample of mercury is found to have a mass of 453.0453.0 g and a volume of 33.4833.48 mL
Answer:
13.53 g/mL
Explanation:
We can calculate the density of an object if we are given its mass and its volume, using the following equation:
Density = Mass / VolumeWe input the data given by the problem:
Density = 453.0 g / 33.48 mLDensity = 13.53 g/mLThus the density of the mercury sample is 13.53 g/mL
Suppose 2.07g of sodium iodide is dissolved in 50.mL of a 0.30M aqueous solution of potassium carbonate. Calculate the final molarity of iodide anion in the solution. You can assume the volume of the solution doesn't change when the sodium iodide is dissolved in it. Round your answer to 2 significant digits.
Answer:
0.28M is molarity of iodide anion in the solution.
Explanation:
Molarity is defined as the ratio between moles of solute (In this case, iodine ion), per liter of solution (The total volume of the solution is 50.0mL = 0.0500L).
Thus, we need to convert mass of sodium iodide to moles using its molar mass (Molar mass NaI: 149.89g/mol). Moles of NaI = Moles of I⁻:
Moles NaI = Moles iodide ion:
2.07g * (1mol / 149.89g) = 0.01381moles NaI = Moles I⁻
Molarity is:
0.01381moles I⁻ / 0.0500L =
0.28M is molarity of iodide anion in the solutionQuestion text What is the mole fraction of benzene in a benzene-toluene solution whose vapor pressure is 51 torr at 20°C?
Answer:
Mole fraction for benzene is 0.683
Explanation:
We need to determine the colligative property about vapour pressure which formula is:
ΔP = P° . Xm
where P° is vapour pressure of pure solvent.
ΔP = Vapor pressure of pure solvent - Vapor pressure of solution
In this case, our solvent is benzene and the solute is toluene. For this colligative property vapour pressure of solution is lower than pure solvent.
P° of benzene at 20°C is 74.7 Torr
Xm is the value for the mole fraction of solute.
Let's replace data: 74.7 Torr - 51 Torr = 74.7 Torr . Xm
Xm = 0.317 → That's the mole fraction for toluene.
Then, mole fraction for benzene will be: 1 - 0.317 → 0.683
What volume of gold would be equal in mass to a piece of copper with a volume of 121 mL? The density of gold is 19.3 g/mL; the density of copper is 8.96 g/mL.
Answer:
We are tasked to solve for the volume of Gold given that the mass of Gold is equivalent to that of a copper.
Explanation:
Details:
Density of Copper= 8.96 g/ml
Volume of Copper=141 ml
mass of Gold = mass of Copper
Density of Gold=19.3 g/ml
In order to solve for the mass of copper, we need to use the density formula
Density= mass/volume
Since we are to solve for the mass of copper
mass of copper= Density of Copper * Volume of Copper
mass of copper= 8.96 g/ml* 141 ml= 1263.36 g
Thus,
mass of gold=mass of copper=1263.36 g
Hence,
Using still the density formula to solve for the volume of gold,
Volume of gold=mass of gold/ Density of gold
Volume of gold=1263.36 g/ 19.3 g/ml = 65.46 mL
Therefore, the volume of the gold must be 65.46 mL in order to have the same mass of a copper
Radio waves are used to transmit information on various channels. What is the wavelength of a radio wave having the frequency of 5.40 × 1010 Hz?
Answer:
tyduyfjhg
Explanation:
HELP ASAP ILL GIVE BRAINIEST!!!
1 Describe Sodium (Na) by stating the group number and if it's a metal or nonmetal
2. Describe Helium (He) by stating the group number and it it's a metal or nonmetal
3. Describe lodine by stating the group number and it it's a metal or nonmetal
4 Describe Calcium (Ca) by stating the group number and it it's a metal or nonmetal
5 Name one element that has similar properties to potassium (K)
6. Name one element that has similar properties to magnesium (Mg).
7 Name one element that has similar properties to xeon Xe)
8. Name one element that has similar properties to chlorine (CI)
Answer:
1. the group number of sodium is 1 and it is a metal
2. the group number of helium is 18 and it is a nonmetal
3. the group number of iodine is 17 and it is a nonmetal
4.the group number of calcium is 2 and it is a metal
5. lithium has similar properties to potassium
6. calcium has similar properties to magnesium
7. neon has similar properties to xenon
8. Iodine has similar properties to chlorine
When steam condenses into water, __________. When steam condenses into water, __________. heat is given off by the water no heat is given off or absorbed heat is absorbed by the water
Answer: heat is given off by the water
Explanation:
Condensation can be defined as the process by which water vapors or steam in the atmosphere are converted into liquid water. It is the part of water cycle. The water form water bodies and terrestrial surfaces gets evaporated in the form of water vapors. These vapors rise in the upper atmospheric layers and aggregate to form the clouds when these vapors become heavy they fall down in the form of rain. Heat is given off in this process by the water vapors or steam to be converted in liquid.
A student measures 48.8 mL of concentrated nitric acid, which has a density of 1.55g/ mL. What is the mass of the acid?
The mass of the acid : 75.64 g
Further explanationGiven
volume = 48.8 ml
density = 1.55 g/ml
Required
the mass
Solution
Further explanation
Density is a quantity derived from the mass and volume
Density is the ratio of mass per unit volume
Density formula:
[tex]\large{\boxed {\bold {\rho~=~ \frac {m} {V}}}}[/tex]
Input the value :
mass = ρ x V
mass = 1.55 g/ml x 48.8 ml
mass = 75.64 g
A 2.54 g piece of zinc (density = 7.14 g/mL) is added to a graduated cylinder that contains 12.13 mL h2o. What will be the final volume reading on the graduated cylinder, in mL?
Answer: If I'm correct it's 12.54 mL but don't rely on this because I'm not sure
Explanation:
Answer:
12.49 ml
Explanation:
Density = mass / volume
Volume = mass / density
Volume of zinc = 2.54/7.14
Volume of zinc = 0.3557
Initial volume = 12.13 ml
Total volume = initial volume+ volume of zinc
Total volume = 12.13 + 0.3557
Total volume = 12.4857 = 12.49 ml
A chemist has a block of aluminum metal (density is 2.7 g/mL). The block weighs 2.3 g. What is the volume, in mL, of the aluminum block?
Answer:
0.85 mL
Explanation:
Step 1: Given data
Density of aluminum (ρ): 2.7 g/mLMass of the aluminum block (m): 2.3 gVolume of the aluminum block (V): ?Step 2: Calculate the volume of the aluminum block
Density is an instrisic property. It is equal to the mass of the block divided by its volume.
ρ = m/V
V = m/ρ
V = 2.3 g/(2.7 g/mL)
V = 0.85 mL
Suppose that 25,0 mL of a gas at 725 mmHg and 298K is converted to
273'K and 760 mmHg atm. What would be the new volume? Hinto use the
following gas law equation (p1"V1) /T1 = (p2*V2)/72 "SHOW WORK *
28.15 ml
25.18 ml
21.85 mL
Particles of a liquid"
The new volume : 21.85 ml
Further explanationGiven
V1=25,0 ml
P1=725 mmHg
T1=298K is converted to
T2=273'K
P2=760 mmHg atm
Required
V2
Solution
Combined gas law :
[tex]\tt \dfrac{P_1.V_1}{T_1}=\dfrac{P_2.V_2}{T_2}[/tex]
Input the value :
V2=(P1.V1.T2)/(P2.T1)
V2=(725 x 25 ml x 273)/(760 x 298)
V2=21.85 ml
A 175 g piece of iron and a 175 g piece of aluminum are placed in a hot water bath so that they are warmed to 99.7 o C. The metal samples are removed and cooled to 21.5 o C. Which sample undergoes the greater heat change
Answer:
The Aluminium sample
Explanation:
From the question,
ΔQ of the iron = Cm(t₂-t₁)........................ Equation 1
Given: C = specific heat capacity of iron, m = mass of iron, t₁ and t₂ = initial and final temperature respectively.
Given: m = 175 g = 0.175 kg, t₂ = 21.5°C, t₁ = 99.7°C
Constant: C = 444 J/kgK.
Substitute into equation 1
ΔQ = 0.175(444)(21.5-99.7)
ΔQ = -6076.14 J
Similarly, for aluminium,
ΔQ' = c'm'(t₂-t₁)...................... Equation 2
Given: m' = 175 g = 0.175 kg,
Constant: 900 J/kgK
ΔQ' = 0.175(900)(21.5-99.7)
ΔQ' = -12316.5 J
Hence the aluminium sample undergoes the greater heat change