Calculate the heat energy released when 21.1 g of liquid mercury at 25.00 °C is converted to solid mercury at its melting point.
Constants for mercury at 1 atm
heat capacity of Hg(l) 28.0 J/(mol⋅K)
melting point 234.32 K
enthalpy of fusion 2.29 kJ/mol
Think
about the physical properties used to identify elements as either metal,non-metals, or metalloids. Write
Imagine that you are asked to classify a group of elements as either metal, non-metals, or metalloids.
Explain how you would use their physical properties to accomplish this task.
Be sure to –Address the prompt, provide support, and conclude your thoughts. Write legibly and concisely.
Answer:
The elements can be classified as metals, nonmetals, or metalloids. ... Elements are further classified into metals, non-metals, and metalloids based on their properties, ... when they undergo chemical reactions They normally do not accept ... Most metal oxides are basic oxides and dissolve in water to form .
Explanation:
Is anyone good at chemistry if so can someone help me please ?
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So, litmus paper is a qualitative tool for assessing the acidity or basicity of a substance (usually a solution). In general, blue litmus turns red in the presence of an acid, and red litmus turns blue in the presence of a base. They can't really tell you much more than that.
The solutions that are most likely acids are those that turn blue litmus red and do not evoke a color change in red litmus. A solution that turns red litmus blue or does not evoke a color change in blue litmus is likely not an acid. Using these criteria, solutions 4 and 7 are most likely acids since they both turn blue litmus red (and they cause no color change in red litmus).
The correct answer choice would thus be D.
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If aqueous solutions of Ba(OH)2 and HNO3 are mixed, what products are formed? Select one: a. BaN2(s) + H2O(l) b. Ba(NO3)2(aq) + H2O(l) c. Ba(s) + H2(g) + NO2(g) d. Ba2O(s) + NO2(g) + H2O(l) e. Ba3N2(s) + H2O(l)
Answer: Ba(NO3)2(aq) + H2O(l)
Explanation:
What is the molar mass of AlCl3
Answer:
133.34 g/moles
Explanation:
but to make life easy it could be 133.4 g/ moles as well
A student prepares a aqueous solution of butanoic acid . Calculate the fraction of butanoic acid that is in the dissociated form in his solution. Express your answer as a percentage. You will probably find some useful data in the ALEKS Data resource.
Answer:
15.4%
Explanation:
If Ka = 0.54 mM = 1.51x10⁻⁵
Then;
C₄H₈O₂ --------> C₄H₇O₂⁻ + H⁺
I 0.54x10⁻³ 0 0
E 0.54x10⁻³(1-x) 0.54x10⁻³x 0.54x10⁻³x
Recall that x is the percentage degree of dissociation
From the ICE table;
Ka = [C₄H₇O₂⁻] [ H⁺]/[C₄H₈O₂]
1.51x10⁻⁵=(0.54x10⁻³x) (0.54x10⁻³x)/ 0.54x10⁻³(1-x)
1.51x10⁻⁵ = 0.54x10⁻³x^2/1-x
1.51x10⁻⁵(1-x) = 0.54x10⁻³x^2
1.51x10⁻⁵ - 1.51x10⁻⁵x = 0.54x10⁻³x^2
Hence;
0.54x10⁻³x^2 + 1.51x10⁻⁵x - 1.51x10⁻⁵=0
x^2 + 0.028x - 0.028 = 0
Solving the quadratic equation here;
x = 0.154 or −0.182
Ignoring the negative result, x = 0.154
Hence, fraction of butanoic acid that is in the dissociated form in this solution = 15.4%
How are cells organized?
A: Organs
B: Organelles
C: Tissues
Answer:
tissues,organs, organelles
Be sure to answer all parts.
Find the pH during the titration of 20.00 mL of 0.1000 M triethylamine, (CH3CH2)3N (Kb = 5.2 × 10−4), with 0.1000 M HCl solution after the following additions of titrant.
20.20 mL:
pH =
a.
Initial moles of (CH₃CH₂)₃N = (0.1000 mol/L) × (20.00/1000 L) = 0.002 mol
Moles of HCl added = (0.1000 mol/L) × (13.00/1000 L) = 0.0013 mol
Addition of 1 mole of HCl reacts with 1 mole of (CH₃CH₂)₃N to 1 mole of (CH₃CH₂)₃NH⁺.
After addition of 13.00 mL of HCl:
Moles of (CH₃CH₂)₃N left unreacted = (0.002 - 0.0013) mol = 0.0007 mol
Moles of (CH₃CH₂)₃NH⁺ produced = 0.0013 mol
Hence, [(CH₃CH₂)₃NH⁺]/[(CH₃CH₂)₃N] = 0.0013/0.0007 = 13/7
Consider the dissociation of (CH₃CH₂)₃N:
(CH₃CH₂)₃N(aq) + H₂O(l) ⇌ (CH₃CH₂)₃NH⁺(aq) + OH⁻(aq) …… Kb = 5.2 × 10⁻⁴
Henderson-Hasselbalch equation:
pOH = pKb + log([(CH₃CH₂)₃NH⁺]/[(CH₃CH₂)₃N])
pOH = -log(5.2 × 10⁻⁴) + log(13/7) = 3.55
pH = pKw - pOH = 14.00 - 3.55 = 10.45
====
b.
Initial moles of (CH₃CH₂)₃N = 0.002 mol
Moles of HCl added = (0.1000 mol/L) × (20.80/1000 L) = 0.00208 mol
HCl is in excess.
Moles of HCl left unreacted = (0.00208 - 0.002) mol = 0.00008 mol
Volume of the final solution = (20.00 + 20.80) mL = 40.8 mL = 0.0408 L
In the final solution:
[H₃O⁺] = [HCl] = (0.00008 mol) / (0.0408 L) = 0.00196
pH = -log[H₃O⁺] = -log(0.00196) = 2.71
====
c.
Initial moles of (CH₃CH₂)₃N = 0.002 mol
Moles of HCl added = (0.1000 mol/L) × (29.00/1000 L) = 0.0029 mol
HCl is in excess.
Moles of HCl left unreacted = (0.0029 - 0.002) mol = 0.0009 mol
Volume of the final solution = (20.00 + 29.00) mL = 49 mL = 0.049 L
In the final solution:
[H₃O⁺] = [HCl] = (0.0009 mol) / (0.049 L) = 0.0184
pH = -log[H₃O⁺] = -log(0.0184) = 1.74
Is anyone good at chemistry if so can someone help me please ?
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So, what's shown here is the ion product of pure water: that is, the product of the concentrations of hydronium and hydroxide ions in pure water at 25 °C. By this relation, if you know the [H₃O⁺], you can calculate the [OH⁻], and vice-versa.
Since [H₃O⁺] × [OH⁻] = 1.0 × 10⁻¹⁴, [OH⁻] = (1.0 × 10⁻¹⁴)/[H₃O⁺].
Substituting the given [H₃O⁺] as 1.25 × 10⁻² M:
[OH⁻] = (1.0 × 10⁻¹⁴)/(1.25 × 10⁻² M) = 8.0 × 10⁻¹³ M.
In a simple food chain, a frog eats insects and a snake eats the frog. The primary role of the frog in the food chain is?
Answer:
It is clear from the above food chain that the grass occupies the first topic level which consists of producers. The second tropic level consist of primary consumers which is Insect. And the Frog assign the Third tropic level of food chain consisting of secondary consumers.Explanation:
2 C.H. (g) + 190, (g) → 1200, (g) + 147,0 (8)
Answer:
please your question is not understandable
form a belt between Mars and Jupiter.
A)
Asteroids
B)
Comets
C)
Meteors
D)
Stars
Answer:
A
Explanation:
show by means of equations how to separate mixture of benzoic acid and phenol
Just dissolve all three compounds in an organic solvent which not miscible with water (those two I have mentioned) in separatory funnel. Use aqueous sodium bicarbonate first to extract. If you use sodium hydroxide, both phenol and benzoic acid will be extracted as both can react with hydroxide
I need help with this science problem
Answer:
I'm pretty sure its D
Explanation:
It says the best that explains. D states that when it has less energy that it the molecules will collide. And they would to make a liquid. So thats why its D.
My teacher laid this much out for us but I don’t know how to get the products in each one.
Answer:dang
Explanation:
1.
Why are kilometers not a good unit of measurement in space?
T.
2.
What distance measurement unit is used for objects within our solar system?
astronomical
units
3.
How many kilometers are in one astronomical unit?
4.
What distance measurement unit is used for objects outside of our solar
system?
_light
year!
5.
How many kilometers are in one light-year? I
How far away is the nearest star to Earth other than our Sun?
6.
7.
How far away is the center of the Milky Way Galaxy from Earth?
8.
What is the diameter of the Milky Way Galaxy?