Escaping from the haunted house, Anna ran home immediately to her chemistry lab
back at the high school. After analysis of the gold heart, she found the heart was not
composed of pure gold, but gold (III) oxide (Au203). What percentage (by mass) was
gold in the heart?
a) 10.9% Au
C) 89.1% Au
b) 81.2% Au
d) 92.9% Au
25 ml of 2.4 M K2(CO3) is mixed with 35 ml of 2.0 M Al(NO3)3. (a) Evaluate the moles for each reactant (b) indicate the limiting reactant (c) how many moles of Al2(CO3)3 are formed?
Answer:
a) 0.06 mol K₂(CO₃) and 0.07 mol Al(NO₃)₃
b) The limiting reactant is K₂CO₃
c) 0.03 moles of Al₂(CO₃)₃
Explanation:
The balanced reaction between K₂CO₃ and Al(NO₃)₃ is the following:
3 K₂CO₃ + 2 Al(NO₃)₃ → Al₂(CO₃)₃ + 6 KNO₃
(a) We can calculate the moles for each reactant as the product of the molarity (M) and the volume (V) in liters.
K₂(CO₃): M = 2.4 mol/L , V = 25 mL x 1 L/1000 mL = 0.025 L
⇒ moles K₂(CO₃) = M x V = 2.4 mol/L x 0.025 L = 0.06 mol K₂(CO₃)
Al(NO₃)₃: M = 2.0 mol/L , V = 35 mL x 1 L/1000 mL = 0.035 L
⇒ moles Al(NO₃)₃ = M x V = 2.0 mol/L x 0.035 L = 0.07 mol Al(NO₃)₃
(b) According to the balanced equation, the stoichiometric ratio is 3 moles K₂CO₃/2 moles Al(NO₃)₃. We have 0.07 moles of Al(NO₃)₃, so we multiply the moles of Al(NO₃)₃ by the stiochiometric ratio to calculate how many moles of K₂CO₃ are needed:
0.07 mol Al(NO₃)₃ x 3 mol K₂CO₃/2 mol Al(NO₃)₃ = 0.105 moles of K₂CO₃
We need 0.105 moles of K₂CO₃ but we have only 0.06 moles of K₂CO₃. Therefore, the limiting reactant is K₂CO₃.
(c) We use the limiting reactant to calculate how many moles of product (Al₂(CO₃)₃) are formed. According to the equation, 2 moles of K₂CO₃ produce 1 mol of Al₂(CO₃)₃, thus the stoichiometric ratio is 1 mol Al₂(CO₃)₃/2 moles K₂CO₃. We have 0.06 moles of K₂CO₃, so the number of moles of Al₂(CO₃)₃ will be:
0.06 moles K₂CO₃ x 1 mol Al₂(CO₃)₃/2 moles K₂CO₃ = 0.03 moles of Al₂(CO₃)₃
When writing the chemical formulas for a molecular compound, what method do you use?
Answer:
A molecular compound is usually composed of two or more nonmetal elements. Molecular compounds are named with the first element first and then the second element by using the stem of the element name plus the suffix -ide.
A 15.0 ml sample of gas at 10.0 degree Celsius and 760 torr changes to a pressure of 1252 torr at 35.0 degree Celsius. What is the volume of the gas?
Answer:
9.91 mL
Explanation:
Using the combined gas law equation as follows;
P1V1/T1 = P2V2/T2
Where;
P1 = initial pressure (torr)
P2 = final pressure (torr)
V1 = initial volume (mL)
V2 = final volume (mL)
T1 = initial temperature (K)
T2 = final temperature (K)
According to the information provided in this question;
V1 = 15.0mL
V2 = ?
P1 = 760 torr
P2 = 1252 torr
T1 = 10°C = 10 + 273 = 283K
T2 = 35°C = 35 + 273 = 308K
Using P1V1/T1 = P2V2/T2
760 × 15/283 = 1252 × V2/308
11400/283 = 1252V2/308
Cross multiply
11400 × 308 = 283 × 1252V2
3511200 = 354316V2
V2 = 3511200 ÷ 354316
V2 = 9.91 mL
what are protons, what is their charge, and where they located?
Answer:
Protons are the positive parts in an atom, they are positively charged and they are located in the nucleus of an atom..
Explanation:
prolly not the best explanation but hope it helps <3
Valerie creates a model using three different rocks. The rocks are classified as igneous, metamorphic, and sedimentary.
Which property does Valerie use for classification purposes?
color
formation
shape
texture
The rocks are classified as igneous, metamorphic, and sedimentary use the formation for classification purposes.
What are the 3 types of rocks existing on earth?The outermost of them, called the crust, is composed of three types of rocks: magmatic, sedimentary and metamorphic. They are defined through the origin of several minerals and can be characterized with chemical composition, texture or shape, but the most used specification is based on composition.
The property does Valerie use for classification purposes is formation.
See more about rocks at brainly.com/question/19930528
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water will boil when...
Answer:
C
Explanation:
2 C2H6 + 7 O2 → 4 CO2 + 6 H2O How many moles of oxygen gas (O2) are needed to create EXACTLY 6 moles of Carbon dioxide(CO2)?.
What is the range of pH values in a basic solution?
a.pH=7
b.pH is greater than 7
c.pH is between 0 and 14
d.pH is less than 7
Answer:
b. ph is greatet than 7
Explanation:
ph=7 neutral
ph=7-14 basicity as you go up increase basicity
ph=0-7 acodity as you go down increasing acidity
What is the molarity of a solution where one mole of NaOH is added to 2000mL of water
Answer:
Molarity of a solution where one mole of NaOH is added to 2000mL of water is 0.0005
Explanation:
Molarity is the equal to number of moles of solute divided by total volume of solvent
Given -
Number of moles of solute i.e NaOH = 1
Total volume of solvent i.e water = 2000 mL
Molarity [tex]\frac{1}{2000} = 0.0005[/tex]
CH3OH=CO+H2 Balance the equations and tell the atoms. Giving brainliest
Answer:
CII + 4 e- → C-II (reduction)
4 H0 - 4 e- → 4 HI (oxidation)
Explanation:
Answer:
The correct answer should be:
[blank] CO + [2] H2 => [blank] CH3OH
or
CO + [2] H2 => CH3OH
Show work on how you answer it, please.
Answer:
the frist one is balance
by the side of reactant is
C=8
O=8
H2=17×2=34
from the product side
C=8
O=8×1=8
H2=18+(8×2)=34
and they are balance
the second one is
the reactant side
Fe=4
S=4
O2=7×2=14
the product side of the chemical equation
Fe=3×2=6
S=4
O=(4×2)+(3×3)=6+9=15
it is not balance.
#THE FRIST ONE IS BALANCE.
#THE SECOND ONE IS NOT BALANCE.
Geothermal energy is produced from a combination of high pressure and the breakdown of______ underground.
Fill in the blank
Which two radioisotopes have the same decay mode?
A)220Fr and 60C0
B)37K and 42K
C)37Ca and 53Fe
D)99Tc and 19Ne
Answer:
c
Explanation:
37Ca and 53Fe have the same decay mode.
What are the three common modes of radioactive decay?Three of the most common types of decay are alpha decay (α-decay), beta decay (β-decay), and gamma decay (γ-decay), all of which involve emitting one or more particles.
Which isotopes are most likely to decay?The most likely mode of decay for a neutron-rich nucleus is one that converts a neutron into a proton. Every neutron-rich radioactive isotope with an atomic number smaller than 83 decays by electron emission. C, 32P, and 35S, for example, are all neutron-rich nuclei that decay by the emission of an electron.
Learn more about radioisotopes here https://brainly.com/question/18640165
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Wat two common uses for Zinc???
Answer:
It is used to prevent rusting and corrosion on steel and iron. It is also used for batteries
Explanation:
It is used to prevent rusting and corrosion on steel and iron. It is also used for batteries
Which time shows the lowest composition of all green house gases?
Answer:
1750
Explanation:
Greenhouse gases are those gases that are believed to contribute to the rise in the temperature of the earth by trapping infrared rays close to the surface of the earth.
Prominent among the greenhouse gases are; N2O, methane and CO2.
From the chart, we can see that the lowest sum of concentration of greenhouse gases measured in ppm was obtained in 1750. Thus this period shows the lowest composition of greenhouse gases.
How many grams are there in 5.0 x 10^25 molecules of H2? Round to the tenths places.
Answer:
166.04g
Explanation:
Mass=Moles xRMM
1 mole = 6.023 x10^23molecules
5.0 x10^25molecules
=83.02moles
RMM=2
mass=83.02 x2
and=166.04g
The gas in an aerosol can is at a pressure of 3.16 atm at 32.2°C. What would the gas pressure in the can be at 22.9°C?
Answer:
The pressure of the gas would be 3.06 atm
Explanation:
Amonton's law states that the pressure is directly proportional to the absolute temperature of a gas under constant volume. The equation is:
P1 / T1 = P2 / T2
Where P1 is the initial pressure = 3.16atm
T1 is initial absolute temperature = 273.15 + 32.2°C = 305.35K
P2 is our incognite
And T2 is = 273.15 + 22.9°C = 296.05K
Replacing:
3.16atm / 305.35K = P2 / 296.05K
3.06 atm = P2
The pressure of the gas would be 3.06 atmwhy are metals good conducts of heat??????
Materials that are good conductors of thermal energy are called thermal conductors. Metals are especially good thermal conductors because they have freely moving electrons that can transfer thermal energy quickly and easily
Answer:
Explanation:
Materials that are good conductors of thermal energy are called thermal conductors. Metals are especially good thermal conductors because they have freely moving electrons that can transfer thermal energy quickly and easily.1
If a 0.7 M solution of Ca(OH)2 dissociates completely in water, what is the
final [OH-]?
Answer:
1.40 M [OH⁻]
Explanation:
This compound dissociates into 3 ions, but since we are asked about [OH⁻], it's only 2. Therefore, multiply the molarity of the solution by the number of ions that [OH⁻] dissociates into:
2 × 0.70 M = 1.40 M
Hope this helps! Sorry that you got a link. Those are getting really annoying
Which statement below best describes how the interaction of two systems causes a human arm to bend?
A. The circulatory system sends signals to the nervous system
B. The nervous system sends signals to the muscoskeletal system
C. The circulatory system sends singlas to the musclskeletal system
D. The digestive system sends signals to the nervous system
Answer:
your answer is C I believe
1pt which blood vessel carries waste-rich blood from the capillaries back to the healt?
O A. vein
OB. neuron
O C. vena cava
OD. aorta
Hi can anyone help me ?
Answer:
its 4
Explanation:
SOMEONE HELP PLEASE !!
Which is not an electrolyte
1. Ionic salt
2. Acid
3. Base
4. Water
PLEASE HELP ME
salt is not because it gets u dehydrated
how many formula units are present in 0.354 moles of copper (III) chloride, CuCl2
Answer:
47.596008
Explanation:
Determine the number of representative particles in each of the following:
(a) 0.294 mol silver
____ atoms
(b) 8.98 10-3 mol sodium chloride
____ formula units
(c) 23.3 mol carbon dioxide
____ molecules
(d) 0.310 mol nitrogen (N2)
____ molecules
Answer:
(a) 0.294 mol silver = [tex]1.770 * 10^{23}[/tex]
(b) 8.98 * 10-3 mol sodium chloride - [tex]5.407 *10^{23}[/tex]
(c) 23.3 mol carbon dioxide = [tex]1.403 * 10^{25}[/tex]
(d) 0.310 mol nitrogen (N2) = [tex]1.866 * 10^{23}[/tex]
Explanation:
In one mole there are [tex]6.022 * 10^{23}[/tex] atoms/molecules
(a) 0.294 mol silver = [tex]6.022 * 10^{23} * 0.294 = 1.770 * 10^{23}[/tex]
(b) 8.98 * 10-3 mol sodium chloride - [tex]5.407 *10^{23}[/tex]
(c) 23.3 mol carbon dioxide = [tex]23.3 * 6.022 * 10^{23} = 1.403 * 10^{25}[/tex]
(d) 0.310 mol nitrogen (N2) = [tex]0.310 * 6.022 * 10^{23} = 1.866 * 10^{23}[/tex]
Please answer correctly !!!!! Will mark Brianliest !!!!!!!!!!!!!!
Answer:
I think Sr I think so maybe
name two enzyme used to make alcohol
Answer:
here is your answer
Cellulase and proteases are two enzymes are used for making alcohol
hope it helps you
Explanation:
pwlss giv meh brainless
what is 1 mol / 66.04g
Answer:
15.142338 mol/kg
Explanation:
(1 mole) / (66.04 grams)
HELP ME PLEASE WILL GIVE BRAINLY NO BAD ANSWERS
Answer:
7.17
Explanation:
convert 5.50g to moles of salicylic acid. Then use mole ratios and convert the moles of salicylic acid to moles of Asprin(mole ratio is 1:1). Then convert the moles to grams using the molar mass of asprin.