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
salantis [7]
3 years ago
15

If you heat your melting point tube too quickly, what will your observed melting point be in comparison to the actual melting po

int?
Chemistry
1 answer:
solniwko [45]3 years ago
5 0

Explanation:

When conducting a melting point experiment, if we were to heat a sample quickly. Large amount heat is provided instantly which would melt the crystals in the tube very quickly, even before the temperature of the thermometer reaches to that level. So the observes melting point would be much lower than the actual melting point when sample is heated slowly.

You might be interested in
What is one way scientists can split a substance into its simpler components
notsponge [240]

Answer: By using electrolysis.

Explanation:

Electrolysis is a chemical change produced by sending an electric current through a compound. Electrolysis works because the hydrogen and oxygen ions are held together by an electric attraction.

5 0
3 years ago
Any help would be appreciated. Confused.
masya89 [10]

Answer:

q(problem 1) = 25,050 joules;  q(problem 2) = 4.52 x 10⁶ joules

Explanation:

To understand these type problems one needs to go through a simple set of calculations relating to the 'HEATING CURVE OF WATER'. That is, consider the following problem ...

=> Calculate the total amount of heat needed to convert 10g ice at -10°C to steam at 110°C. Given are the following constants:

Heat of fusion (ΔHₓ) = 80 cal/gram

Heat of vaporization (ΔHv) = 540 cal/gram

specific heat of ice [c(i)] = 0.50 cal/gram·°C

specific heat of water [c(w)] = 1.00 cal/gram·°C

specific heat of steam [c(s)] = 0.48 cal/gram·°C

Now, the problem calculates the heat flow in each of five (5) phase transition regions based on the heating curve of water (see attached graph below this post) ...   Note two types of regions (1) regions of increasing slopes use q = mcΔT and (2) regions of zero slopes use q = m·ΔH.

q(warming ice) =  m·c(i)·ΔT = (10g)(0.50 cal/g°C)(10°C) = 50 cal

q(melting) = m·ΔHₓ = (10g)(80cal/g) 800 cal

q(warming water) = m·c(w)·ΔT = (10g)(1.00 cal/g°C)(100°C) = 1000 cal

q(evaporation of water) =  m·ΔHv = (10g)(540cal/g) = 5400 cal

q(heating steam) = m·c(s)·ΔT = (10g)(0.48 cal/g°C)(10°C) = 48 cal

Q(total) = ∑q = (50 + 800 + 1000 + 5400 + 48) = 7298 cals. => to convert to joules, multiply by 4.184 j/cal => q = 7298 cals x 4.184 j/cal = 30,534 joules = 30.5 Kj.

Now, for the problems in your post ... they represent fragments of the above problem. All you need to do is decide if the problem contains a temperature change (use q = m·c·ΔT) or does NOT contain a temperature change (use q = m·ΔH).    

Problem 1: Given Heat of Fusion of Water = 334 j/g, determine heat needed to melt 75g ice.

Since this is a phase transition (melting), NO temperature change occurs; use q = m·ΔHₓ = (75g)(334 j/g) = 25,050 joules.

Problem 2: Given Heat of Vaporization = 2260 j/g; determine the amount of heat needed to boil to vapor 2 Liters water ( = 2000 grams water ).

Since this is a phase transition (boiling = evaporation), NO temperature change occurs; use q = m·ΔHf = (2000g)(2260 j/g) = 4,520,000 joules = 4.52 x 10⁶ joules.

Problems containing a temperature change:

NOTE: A specific temperature change will be evident in the context of problems containing temperature change => use q = m·c·ΔT. Such is associated with the increasing slope regions of the heating curve.  Good luck on your efforts. Doc :-)

5 0
3 years ago
C₇H₆O₂ + O₂ -->CO₂ +H₂O Find the chemical reaction
lions [1.4K]

Answer:

Air

Explanation:

idrk im just an idiot

3 0
2 years ago
Read 2 more answers
A jeweler guarantees that a piece of jewelry is at least 95% gold, by mass. You consider buying a piece of gold jewelry that wei
ELEN [110]
The density of the sample is:
Density = mass / volume
Density = 9.85 / 0.675
Density = 14.6 g/cm³

If the sample has 95% gold, and 5% silver, its density should be:
0.95 x 19.3 + 0.05 x 10.5
Theoretical density = 18.9 g/cm³

The difference in theoretical and actual densities is very large, making it likely that the jeweler was not telling the truth.
8 0
3 years ago
PLs heLp Me
olchik [2.2K]

Answer:

Opaque → a.no light travels through the material; all light is reflected or absorbed

Translucent → b.some light travels through the material and the image cannot be seen clearly

Transparent → c.all light travels through the material and the image can be seen clearly

Explanation:

Hope this helps :)

7 0
2 years ago
Read 2 more answers
Other questions:
  • Why and how are acids and bases important?
    6·1 answer
  • List the elements in the increasing order of their electronegativity. Give reasons for your answer.
    11·1 answer
  • Acids and bases can neutralize each other in double displacement reactions. For example, if hydrogen chloride (a strong acid, HC
    9·1 answer
  • The model below shows an atom of an element. 10 light gray and 8 dark gray balls sit at the center with 2 concentric black rings
    16·2 answers
  • How much heat is evolved when 22.5 grams of a food sample changes the temperature of 0.42 kg of water by 4.4 degree C. Assume sp
    13·1 answer
  • Which of the following is not a feature of iron (III) oxide?
    10·2 answers
  • What is the pH of an aqueous solution that has a hydroxide ion concentration of 1.0 x 10^-5 M?​
    11·1 answer
  • When calcium chloride and baking side is mixed, is it an example of chemical or physical change?
    8·1 answer
  • The theory of plate tectonics was, at first, rejected by most scientists. Now most geologists accept that tectonic plates exist
    14·2 answers
  • What pressure (in atm) is required to contain 0.034 moles of oxygen gas in a 5.1 L container at a temperature of 25.00C
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!