Answer:
Non-renewable resources, such as coal and oil, are the primary source of power in the world, and they are used to power vehicles, factories, and homes. Although affordable, they can be harmful to the environment and are one of the notable contributors to global warming.
Explanation:
source:cfi
Magnesium (used in the manufacture of light alloys) reacts with iron(III) chloride to form magnesium chloride and iron. A mixture of 41.0 g of magnesium and 175.0 g of iron(III) chloride is allowed to react. Identify the limiting reactant and determine the mass of the excess reactant present in the vessel when the reaction is complete. Select one: a. Limiting reactant is Mg; 7.4 g of FeCl3 remain. b. Limiting reactant is Mg; 46.5 g of FeCl3 remain. c. Limiting reactant is FeCl3; 1.7 g of Mg remain. d. Limiting reactant is FeCl3; 37.8 g of Mg remain. e. Limiting reactant is Mg; 134.0 g of FeCl3 remain.
Answer:
Limiting reactant is FeCl3; 1.7 g of Mg remain.
Explanation:
From the question;
The equation is;
3Mg(s) + 2FeCl₃(s) → 3MgCl₂(s) + 2Fe(s)
Amount of Mg = 41 g/24.31 g/mol = 1.687 moles
The limiting reactant yields the least amount of MgCl2
3 moles of Mg yields 3 moles of MgCl2
Hence 1.687 moles of Mg yields yields 1.687 moles of MgCl2
FeCl₃ = 175 g/162.2 g/mol = 1.0789 moles
2 moles of FeCl3 yields 3 moles of MgCl2
1.0789 moles of FeCl3 yields 1.0789 * 3/2 = 1.61835 moles of MgCl2
Hence FeCl3 is the limiting reactant
3 moles of Mg reacts with 2 moles of FeCl3
x moles of Mg reacts with 1.0789 of FeCl3
x = 3 * 1.0789 /2 = 1.61835 moles of Mg
Mass of Mg reacted = 1.61835 moles * 24.31 = 39.342 g
Mass of excess Mg = 41 g - 39.342 g = 1.7 g
If 10.5 g of iron, at 25°C, absorbs 128 J of heat, what will be the final temperature of metal? (The specific heat of iron is 0.449 J g-1 °C-1)
Answer:
27.5°C = Final Temperature of the metal
Explanation:
The change in temperature using the specific heat of a material could be obtained using the formula:
Q = m*S*ΔT
Where Q is heat absorbed in Joules = 128J in the problem
m is the mass of the substance = 10.5g
S is Specific Heat of the substance = 0.449J/g°C for Iron
ΔT is change in temperature = Final T - Initial T
Replacing:
128J = 10.5g*0.449J/g°C*ΔT
2.5°C = ΔT
2.5°C = Final T - 25°C
27.5°C = Final Temperature of the metal
Find the number of grams in 16.95 mol hydrogen peroxide (H2O2). Round your
answer to two decimal places and be sure to include the proper units.
Answer: There are 576.46 number of grams present in 16.95 mol hydrogen peroxide [tex](H_{2}O_{2})[/tex].
Explanation:
Number of moles is defined as the mass of substance divided by its molar mass.
The molar mass of [tex]H_{2}O_{2}[/tex] is 34.01 g/mol. Hence, mass of hydrogen peroxide present in 16.95 moles is calculated as follows.
[tex]Moles = \frac{mass}{molarmass}\\16.95 mol = \frac{mass}{34.01 g/mol}\\mass = 576.46 g[/tex]
Thus, we can conclude that there are 576.46 number of grams present in 16.95 mol hydrogen peroxide [tex](H_{2}O_{2})[/tex].
How many moles are there in 8.25 x 10^26 molecules of methane (CH4)?
Answer:
i dont know
Explanation:
because i dont know 45
Add coefficients to balance the equation to make water.
H2(g) +O2 (g)H20 (1)
Answer:
2H2+2O2=2H2O
Explanation:
hope this helps
Identify the limiting reactant when 2.20 g of calcium reacts with 4.5 g of chlorine gas to produce calcium chloride. Write a balanced equation before starting.
I"LL GIVE YOU 30 POINTS AND NAME YOU BRAINLIEST IF YOU ANSWER THIS FOR MEEEEE PLZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ ITS FOR MY STUDY GUIDE!!!!!!
Answer:
2.20*4.5=?? you have to solve the multiplication ok, or its not learning
Explanation:
What are the consequences of purposely having an excess of one of the reactants?
Answer:
When one reactant is in excess, there will always be some left over. The other reactant becomes a limiting factor and controls how much of each product is produced. While using excess reactants can help to increase percentage yields, this is at the expense of atom economy.
Explanation:
Concerning the disposal of materials at the end of the experiment, which methods are safe? Check all that apply.
[ANSWERS]
B. Dispose of pH paper in the trash.
C. Dump the cabbage indicator solution down the drain.
D. Ask your teacher to neutralize the acids and bases before disposal.
Answer:
B. Dispose of pH paper in the trash.
C. Dump the cabbage indicator solution down the drain.
D. Ask your teacher to neutralize the acids and bases before disposal.
Explanation:
Safe disposal of waste means disposal of waste in such a way that it does not pose a threat to the environment.
When pH paper is properly disposed in the trash, it does not constitute any risk to the environment.
When a cabbage indicator solution is disposed down the drain it does not contaminate the environment. It moves directly into the sewers and is properly disposed.
When acids and bases are properly neutralized before disposal, they don't lead to acid or base contamination of the environment.
Which of the following represents alpha decay?
Answer: b
Explanation: alpha decay or particle consist of two protons and two neutrons hence it is a helium nucleus.
An alpha particle [tex]\binom {4} {2}[/tex]He is produced in alpha decay reactions, while the parent nucleus' atomic number and mass number drop by 2 and 4 correspondingly.
Alpha decay:Alpha decay is a nuclear process whereby an unstable nuclear transforms into a different element by ejecting particles composed of two protons and two neutrons. The alpha particle also referred to as a helium nucleus, is the expelled unit of matter. Alpha particles have large masses and electrostatic attraction.An atomic number decreases by 2 and the atomic weight drops by 4 when a radioactive nucleus disintegrates by emitting [tex]\bold{\alpha}[/tex] particle.Therefore, the final answer is "Option B".
Find out more about the alpha decay here:
brainly.com/question/14081292
A sample of helium has a volume of 3.49 L at 741 mmHg. What would be the volume if the pressure
were changed to 760 mmHg at the same temperature?
show work
P1: 741 mmHg
V1: 3.49 L P1 x V1 / P2= (741 mmHg) (3.49 L) / 760 mmHg = 3.40 L
P2: 760 mmHg
V2: ? L
Question: How do we read chemical formulas?
Any molecule can be represented by a formula that lists all the atoms in that molecule. Each element is represented by its atomic symbol in the Periodic Table – e.g. H for hydrogen, Ca for calcium. If more than one atom of a particular element is present, then it’s indicated by a number in subscript after the atomic symbol — for example, H2O means there are 2 atoms of hydrogen and one of oxygen.
If there is more than one of whole groups of atoms, then that’s shown with a bracket around them. For example, calcium hydroxide has one calcium (Ca) for every two hydroxides (OH), so is written as Ca(OH)2.
If a charge is present, it’s indicated in superscript, with a sign (+/-) and a number if more than one charge is present. For example, calcium ions have two positive charges so are written Ca2+.
Sometimes a formula can be written in a way that gives an indication of the structure. A chemical equation shows a reaction taking place. On the left-hand side are the reactants, the molecules that take part in the reaction. On the right-hand side are the products, the molecules that are created in the reaction. Each side must contain the same number of each kind of atom. An arrow between them indicates the direction the reaction is expected to occur:
Ca + Cl2 → CaCl2
Calcium + chlorine → Calcium chloride
If there are two or more of any molecules, that’s indicated with a number in front of the molecule:
CH4 + 2O2 → CO2 + 2H2O
One methane molecule + two oxygen molecules → one carbon dioxide molecule and two water molecules
An equation may sometimes specify which phase each molecule is in – whether it’s solid, liquid, or gas, or if it’s dissolved. This is written in brackets after the molecule – (s) for solid, (l) for liquid, (g) for gas, and (aq) for ‘aqueous’, meaning dissolved in water. For example, solid calcium carbonate reacts with carbonic acid in water to form calcium bicarbonate, which is much more soluble so becomes dissolved in water:
CaCO3 (s) + H2CO3 (aq) → Ca(HCO3)2 (aq)
Solid calcium carbonate + dissolved carbonic acid → dissolved calcium bicarbonate
All chemical reactions can actually proceed in either direction. Most of the time, one direction is expected to take place more strongly, so the arrow is written in that direction. However, many common reactions happen in both directions simultaneously, creating an equilibrium where the reactions are taking place but there is no net change in concentration from one side to the other. This is indicated with the symbol ⇌.
For example, carbonic acid in water is continually breaking down into bicarbonate and hydrogen ions – but the ions are also continually joining back together.
H2CO3 ⇌ HCO3– + H+
Carbonic acid ⇌ bicarbonate + hydrogen ions
What can you say about the forces between the particles of these gases)
Answer:
Gas – In a gas, particles are in continual straight-line motion. The kinetic energy of the molecule is greater than the attractive force between them, thus they are much farther apart and move freely of each other. In most cases, there are essentially no attractive forces between particles.
Explanation:hopes this helps:)
Whch is more acidic, a solution with a pH of 2 or 5
Answer:
A solution with a pH of 2
Explanation:
The lower a pH is in a liquid, the more acidic it is. 7 is the neutral pH for a liquid. We usually drink around that pH for water. A pH higher than 7 expresses that the liquid is a base.
Answer:
A solution with a pH of 2 is more acidic.
Explanation:
The solution with a pH of 2 is more acidic because on the pH scale as you get closer to zero, the more acidic the solution becomes.
What are the only types of metals that be magnetized?
Which type of changes are melting, freezing, and boiling?
Answer:
the changes are physical changes
A gas has a temperature of 14 °C, and a volume of 4.5 liters. If the temperature is raised to 29
°C and the pressure is not changed, what is the new volume of the gas
The new volume of the gas wii be 4.7 liters.
When a solute is added to water, the boiling point
Answer:
Boiling-point elevation describes the phenomenon that the boiling point of a liquid (a solvent) will be higher when another compound is added, meaning that a solution has a higher boiling point than a pure solvent. This happens whenever a non-volatile solute, such as a salt, is added to a pure solvent, such as water.
What is the molarity of a solution made of 2.45 moles of LiCl in 4.75 L of solution?
Answer:
.52 M
Explanation:
moles ÷ liters = molarity
2.45 ÷ 4.75 = 0.5157894737
rounding it = .52
At a high concentration do you have more or less particles per unit volume
Answer:
More particles per unit volume
Explanation:
Concentration means the amount of solute in a solution. Now, the amount of solute also means the number of particles of solute present in a solution.
Hence, when we use the term "high concentration", we imply that the amount of solute present or the number of particles present in a solution is high.
Thus, at high concentration, there are more solute particles than solvent particles in a solution.
I don't understand with the question number 4, does anybody understand how to do it?
Answer:
iodine = I
sodium= Na
oxygen= O2
aluminum = AI
nitrogen=N
sulfur= S
bromine =Br
magnesium =Mg
7. Which structural formula correctly represents a hydrocarbon molecule?
Answer:
the 4th one is the corrent one
HELP ASAP 10 POINTSSS
In this diagram, the medium on top is air and the medium on bottom is glass. Which vocab word best describes what is happening when the light wave passes from the air into the glass?
Question 2 options:
resolution
diffraction
refraction
reflection
Answer: refraction
Explanation: this is because during refraction light moves from one medium to another.
Which forward reaction shows an increase in entropy (disorder)?explain
A.H2(g) + CuO (s) --> H2O(l) + Cu(s)
B.HCl(g) + NH3(g) --> NH4Cl(s)
C.CaCO3(s) -> CaO(s) + CO2g)
D.H2O(g) + O2(g) --> 2H2O)
Explanation:
Entropy also increases when solid reactants form liquid products. Entropy increases when a substance is broken up into multiple parts. The process of dissolving increases entropy because the solute particles become separated from one another when a solution is formed. Entropy increases as temperature increases. S = entropy
k_{b} = Boltzmann constant
\ln = natural logarithm
\Omega = number of microscopic configurations
What is the pressure of the gas if we have 3.50 moles of helium at -50.0°C
in a rigid container whose volume is 25.0 liters?
003 kPa
-58.2 kPa
259.6 kPa
0.0 kPa
Answer:
259.6kPa
Explanation:
because it is big
Bacteria live on skin of humans. The bacteria receive food and shelter form human beings. Most bacteria are harmless and pose little or no threat to humans. This is an example of
Answer: symbiotic relationship
Explanation:
Hydrogen gas can be produced in the laboratory by the reaction of magnesium metal with hydrochloric acid, according to the following equation:
Mg(s) + 2HCl(aq) --> MgCl2(aq) + H2(g)
a. How many grams of hydrogen can be produced when 4.00 g of HCl is added to 3.00 g of Mg?
b. Assuming STP, what is the volume of this hydrogen?
Answer: 0.11 g H2
Explanation: just took test and got it right
Can someone help me with these answers please I’ll give Brainly !!!!
1.What's the first thought that comes to mind when you hear "nuclear"? nuclear, that's the word. well the first thing that comes into everyone's mind in nuclear and they have to think it then think of words that associate with it.
2.the most important point of something.
3.test site
4.
How many moles are in 2.8x10^24 atoms of silicon?
Answer:
4.6 mol Si
General Formulas and Concepts:
Atomic Structure
Reading a Periodic TableMolesAvogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.Stoichiometry
Using Dimensional AnalysisExplanation:
Step 1: Define
[Given] 2.8 × 10²⁴ atoms Si
[Solve] moles Si
Step 2: Identify Conversions
Avogadro's Number
Step 3: Convert
[DA] Set up: [tex]\displaystyle 2.8 \cdot 10^{24} \ atoms \ Si(\frac{1 \ mol \ Si}{6.022 \cdot 10^{23} \ atoms \ Si})[/tex][DA] Divide [Cancel like units]: [tex]\displaystyle 4.64962 \ mol \ Si[/tex]Step 4: Check
Follow sig fig rules and round. We are given 2 sig figs.
4.64962 mol Si ≈ 4.6 mol Si
On a hot day, a 15.0 kg window increased from 20.0 degrees C to 26.7 degrees C. How much heat energy did the glass window absorb? (specific heat of glass = 0.840 J/gC)
Answer: The heat energy absorbed by glass window is 84420 J.
Explanation:
Given: Mass = 15 kg (1 kg = 1000 g) = 15000 g
Initial temperature = [tex]20^{o}C[/tex]
Final temperature = [tex]26.7^{o}C[/tex]
Specific heat capacity = [tex]0.840 J/g^{o}C[/tex]
Formula used is as follows.
[tex]q = m \times C \times (T_{2} - T_{1})[/tex]
where,
q = heat energy
m = mass of substance
C = specific heat capacity
[tex]T_{1}[/tex] = initial temperature
[tex]T_{2}[/tex] = final temperature
Substitute the values into above formula as follows.
[tex]q = m \times C \times (T_{2} - T_{1})\\ q = 15000 g \times 0.840 J/g^{o}C \times (26.7 - 20)^{o}C\\q = 84420 J[/tex]
Thus, we can conclude that the heat energy absorbed by glass window is 84420 J.
Helppppppppp pweaseeeee
Answer:
Explanation:
b