Answer:
a. True
Explanation:
The bond angle for methane is the angle determined by two consecutive hydrogen atoms and the central carbon atom.
Methane, a tetrahedron has the structural formula:
H
|
H - C - H
|
H Methane, CH4
The bond angle is the angle between the H-C-H atoms and is 109.5degrees.
Fires mostly frequently occur in the kitchen true or false
HELP ASAP
Acetylene gas is often used in welding torches because of the very high heat produced when it reacts with oxygen gas, producing carbon dioxide gas and water vapor. Calculate the moles of oxygen needed to produce of water. Be sure your answer has a unit symbol, if necessary, and round it to the correct number of significant digits.
Answer:
0.225 mol = 0.23 mol to 2 significant figures
Explanation:
Calculate the moles of oxygen needed to produce 0.090 mol of water
The equation of the reaction is given as;
2 C2H2 + 5 O2 --> 4 CO2 + 2 H2O
From the equation of the reaction;
5 mol of O2 produces 2 mol of H2O
x mol of O2 produces 0.090 mol of H2O
5 = 2
x = 0.090
x = 0.090 * 5 / 2
x = 0.225 mol
The following aqueous solutions of are mixed: 100.0 mL of 1.00 M lithium bromide and 100.0 mL of 1.00 M lead (II) nitrate. In an organized and clear manner, show all of your work and answers for this problem on the uploaded work. (a) Write the molecular equation for this reaction. (b) Write the total ionic chemical equation for this reaction. (c) Write the net ionic chemical equation for this reaction. (d) Identify the spectator ions in this reaction. (e) Identify the limiting reactant. (f) Determine the mass of solid product that is formed?
Answer and Explanation:
(a) When lithium bromide (LiBr) solution is mixed with a solution of lead (II) nitrate (Pb(NO₃)₂), lithium nitrate (LiNO₃) and lead (II) bromide (PbBr₂) are formed, according to the following molecular equation:
2LiBr(aq) + Pb(NO₃)₂(aq) → 2LiNO₃(aq) + PbBr₂(s) ↓
As the product PbBr₂ is an insoluble solid, it precipitates (↓).
(b) The total ionic equation is written with all ions of the reaction - no matter if they participate in the precipitate formation or not:
2Li⁺(aq) + 2Br⁻(aq) + Pb²⁺(aq) + 2NO₃⁻(aq) → 2Li⁺(aq) + 2NO₃⁻(aq) + PbBr₂(s)
(c) The net ionic equation is written including only the ions which participate in the precipitate formation. In this case, the precipitate is PbBr₂, and it is formed by Pb²⁺ and Br⁻ ions:
Pb²⁺(aq) + 2Br⁻(aq) → PbBr₂(s)
(d) The spectator ions are those which do not participate in the formation of the precipitate. From the total ionic equation, we can see that Li⁺ and NO₃⁻ ions are repeated on both sides of the equation, so they are redundant. Thus, the spectator ions are Li⁺ and NO₃⁻ ions.
(e) To identify the limiting reactant, we first calculate the moles of each compound as the product of the solution concentration and volume:
For LiBr:
C = 1.00 M = 1 mol/L
V = 100.0 mL x 1 L/1000 mL = 0.1 L
moles of LiBr = 0.1 L x 1.00 mol/L = 0.1 mol
The same for Pb(NO₃)₂:
C = 1.00 M = 1 mol/L
V = 100.0 mL x 1 L/1000 mL = 0.1 L
moles of Pb(NO₃)₂ = 0.1 L x 1.00 mol/L = 0.1 mol
From the total ionic equation, we can see that 2 mol of LiBr reacts with 1 mol of Pb(NO₃)₂ to give 1 mol of PbBr₂ (solid product). The stoichiometric molar ratio is 2 mol LiBr/1 mol Pb(NO₃)₂ and we have 0.1 mol of each reactant (0.1 mol LiBr/0.1 mol Pb(NO₃)₂= 1). As 2 mol LiBr/mol Pb(NO₃)₂ > 1 mol LiBr/mol Pb(NO₃)₂, LiBr is the limiting reactant.
(f) From the total ionic equation, we know that 2 moles of LiBr produce 1 mol of PbBr₂. To determine the mass of solid product (PbBr₂) formed, we first multiply the stoichiometric ratio (1 mol PbBr₂/2 mol LiBr) by the actual number of moles of limiting reactant we have (0.1 mol):
moles of PbBr₂ = 0.1 mol LiBr x (1 mol PbBr₂/2 mol LiBr) = 0.05 mol PbBr₂
Finally, we convert the moles of PbBr₂ to gram by using the molar mass of the compound:
Molar mass PbBr₂ = 207.2 g/mol + (2 x 79.9 g/mol) = 367 g/mol
grams of PbBr₂ = 0.05 mol x 367 g/mol = 18.35 g
What will a child given a vaccine hopefully develop?
O A. Antibiotic Resistance
OB. Immunity
0
C. Mutages
D. Increased Growth
Answer:
B (immunity) is the answer
Write the chemical formula for this molecule O=N-CI
Explanation:
Structural Formulas v. Empirical Formulas
An empirical formula (like a molecular formula) lacks any structural information about the positioning or bonding of atoms in a molecule. It can therefore describe a number of different structures, or isomers, with varying physical properties. For butane and isobutane, the empirical formula for both molecules is C2H5, and they share the same molecular formula, C4H10. However, one structural representation for butane is CH3CH2CH2CH3, while isobutane can be described using the structural formula (CH3)3CH.
Number of liters in 0.50 moles of O2
Answer:
there are about 11.2 liters
Why does heating increase the speed at which a solute dissolves in water?
O A. It decreases the surface area of the solute.
B. It prevents the solute from cristallizing.
O c. It makes the water molecules move faster.
D. It raises the pressure of the water molecules.
Answer: C
Explanation:
It gives kinetic energy to the molecules and it breaks the bonds faster because they jiggle more
With the given chemical compounds, what is the balanced chemical equation when lit with fire?
Answer:
Russia es el mejor pais? Vladimir Putin, es el mejor presidente del mundo
How much heat energy is required to raise the temperature of 0.362 kg of copper from 23.0 ∘C to 60.0 ∘C? The specific heat of copper is 0.0920 cal/(g⋅∘C) .
Answer:
83
Explanation:
23+60=83
What does an ion have that an atom does not?
Answer:
Atoms are neutral; they contain the same number of protons as electrons. By definition, an ion is an electrically charged particle produced by either removing electrons from a neutral atom to give a positive ion or adding electrons to a neutral atom to give a negative ion.
Explanation:
:)
An unknown solid is added to water in a calorimeter. The temperature of the water increases. What does this say about the reaction? A) The reaction is exothermic. B) The reaction is endothermic. C) The reaction has absorbed heat from the solution. D) The reaction has released heat to the solution. E) Both A and D are correct.
Answer:
Option A is correct.
Option D is correct.
E is the correct answer
Explanation:
This a theoretical calorimetry problem that can be solved by thermodynamic concepts.
Our system is the unknown solid. If the temperature of water has increased, we can think, that the heat from the metal was absorbed by water, which is our surrounding. If in the analysis of the situation we use a calorimeter, knowing that it is an isolated system, which does not allow the entry or exit of heat, we can conclude that the heat released is equal to the heat absorbed.
In conclusion, the thermodynamic system is constituted by the chemical reaction. In this case, the surrounding is made up of water and the calorimeter itself.
If the reaction is exothermic, the heat released by the reaction will be absorbed by the surrounding . Then, the final temperature will be higher than the initial temperature. If the reaction is endothermic, the heat absorbed by the reaction will be released by the environment. So, the final temperature will be lower than the initial temperature.Sulfuric acid, H 2 S O 4 , is an important industrial chemical, typically synthesized in a multi-step process. What is the percent yield if a batch of H 2 SO 4 has a theoretical yield of 3.9 kg, and 2.8 kg are obtained at the end of the process
Answer:
71.8%
Explanation:
The percent yield of a process or a chemical reaction is calculated as:
percent yield = actual yield/theoretical yield x 100%
From the problem we have:
theoretical yield = 3.9 kg
actual yield = 2.8 kg
Thus, we calculate the yield of H₂SO₄ production as follows:
percent yield = (2.8 kg/3.9 kg) x 100 = 71.79 % ≅ 71.8%
What is the edge length of a 377-g iron cube? (The density of iron is 7.86 g/cm^3, and the volume of a cube is equal to the edge length cubed.)
Answer:3.50 cm
Explanation:
Answer:
3.63cm
Explanation:
Which of the following are correct for zero-order reactions?
A. A higher concentration of reactants will not increase the reaction rate.
B. The units for the rate constant and the rate of reaction are the same.
C. The rate of reaction does not equal the rate constant.
D. The concentration of the reactants changes nonlinearly.
E. A zero-order reaction slows down as the reaction proceeds.
Answer:
The answer is "Choice A and Choice B"
Explanation:
The Zero-Order reactions are usually found if a substrate, like a surface or even a catalyst, is penetrated also by reactants. Its success rate doesn't depend mostly on the amounts of the various reaction in this reaction.
Let the Rate = k
As [tex]\frac{dx}{dt} \ rate\ \ K_0[/tex] doesn't depend on reaction rate, a higher reaction rate does not intensify the reaction.
By the rate [tex]k_0 =\frac{dx}{dt},[/tex] the created based and the reaction rate is about the same.
Below statement are correct about zero order reaction.
higher concentration of reactants will not increase the reaction rate. The units for the rate constant and the rate of reaction are the same. What is Zero order reaction?Zero-order reaction is a chemical reaction in which the rate of chemical reaction does not change with increase or decrease in the concentration of the reactants.
Example is the decomposition of ammonia to nitrogen and hydrogen. the rate does not vary, it is the same.
Therefore, Below statement are correct about zero order reaction.
higher concentration of reactants will not increase the reaction rate. The units for the rate constant and the rate of reaction are the same.Learn more about zero order reaction from the link below.
https://brainly.com/question/13314785
This group of fungi forms spores in a round structure on the end of a hyphae
Answer:
Is zygote fungi an option??
Answer:
zygote fungi
Explanation:
i got the answer right
The mineral content of rocks helps to
classify them.
B
weigh them.
с
melt them.
D
find them.
Answer:
Explanation:
The rocks are composed of mineral grains combined in different ways and having various properties. Minerals are naturally occurring chemical compounds in which atoms are arranged in three-dimensional patterns.
For the reaction C + 2H2 → CH4, how many grams of hydrogen are required to produce 13.1 moles of methane, CH4 ?
Round your answer to the nearest tenth. If your answer is a whole number like 4, report the answer as 4.0
Answer:
7.0
Explanation:
What is the mole ratio between H2O and O2
Which statement best defines the resistance of an electric circuit?
it limits the amount of electrical energy that can pass through a circuit.
It is the amount of electrical energy that is available in a circuit
It is the measurement of the rate of electrical energy in a circuit.
It describes how much electrical energy passes in a circuit.
Answer:
electric circuits can be dangerous
Explanation:
Answer:
The first one
it limits the amount of electrical energy that can pass through a circuit.
Liquid octane CH3CH26CH3 will react with gaseous oxygen O2 to produce gaseous carbon dioxide CO2 and gaseous water H2O. Suppose 2.3 g of octane is mixed with 12.4 g of oxygen. Calculate the minimum mass of octane that could be left over by the chemical reaction. Round your answer to 2 significant digits.
Answer: Octane will be used completely.
Explanation:
To calculate the moles :
[tex]\text{Moles of solute}=\frac{\text{given mass}}{\text{Molar Mass}}[/tex]
[tex]\text{Moles of octane}=\frac{2.3g}{114g/mol}=0.0202moles[/tex]
[tex]\text{Moles of oxygen}=\frac{12.4g}{32g/mol}=0.388moles[/tex]
The balanced chemical reaction will be
[tex]2C_8H_{18}+25O_2(g)\rightarrow 16CO_2(g)+18H_2O(g)[/tex]
According to stoichiometry :
2 moles of octane require = 25 moles of [tex]O_2[/tex]
Thus 0.0202 moles of octane will require=[tex]\frac{25}{2}\times 0.0202=0.2525moles[/tex] of [tex]O_2[/tex]
Thus octane is the limiting reagent as it limits the formation of product and [tex]O_2[/tex] is the excess reagent.
Thus octane will be used completely.
QUESTION 5
Which of the following is NOT electromagnetic wave?
O A. Sound wave.
O B. Microwave.
O C. Infrared wave.
O D. X-Ray.
Answer:
Beta Rays
Beta Rays are not Electromagnetic Waves
Beta rays also known as beta radiation is obtained through the emission of an electron. Beta rays are not electromagnetic waves because they are charged particles and are capable of getting deflected by the magnetic field.
is magnesium oxide an ionic or covalent compound. what are the reasons?
Answer:
ionic
Explanation:
the bonds that hold magnesium and oxygen together are formed between atoms that give electrons
what is a row of elements across the periodic table called
Answer:
a period
Explanation:
Answer: The row of elements across the periodic table is called "periods".
Explanation:
In the Periodic Table, there are seven rows of elements, which is called periods.
A bottle of viranin water contains 3500 mg of potassium in 591.5 mg of H2O. What is the concentration of potassium by mass percent
Answer: 085.5%
Explanation:
The mass fractions of a mixture of gases are 15 percent nitrogen, 5 percent helium, 60 percent methane, and 20 percent ethane with a total mixture molecular weight of 16.12 kg/kmole. Determine the mole fraction of each constituent, the partial pressure of each constituent when the mixture pressure is 1200 kPa and the apparent specific heats of the mixture when the mixture is at room temperature.
Answer:
Explanation:
mass fraction N₂ : He : CH₄ : C₂H₆ : : 15 : 5 : 60 : 20
mole fraction N₂ : He : CH₄ : C₂H₆ : : 15/28 : 5/4 : 60/16 : 20/30
mole fraction N₂ : He : CH₄ : C₂H₆ : : .5357 : 1.25 : 3.75 : .67
Total mole fractions = .5357 + 1.25 + 3.75 + 0.67 = 6.2057
mole fraction of N₂ = .5357 / 6.2057 = .0877
mole fraction of He = 1.25 / 6.2057 = .20
mole fraction of CH₄ = 3.75 / 6.2057 = .6043
mole fraction of C₂H₆ = .67 / 6.2057 = .108
Partial pressure = total pressure x mole fraction
Partial pressure of N₂ = 1200 kPa x .0877 = 105.24 kPa
Partial pressure of He = 1200 kPa x .20 = 240 kPa
Partial pressure of CH₄ = 1200 kPa x .6043 = 725.16 kPa
Partial pressure of C₂H₆ = 1200 kPa x .108 = 129.6 kPa
A student assembles ball bearings that are 0.19 inches in diameter into an FCC lattice using glue which makes for a 0.001 inch thick bond between bearings. What is the lattice constant in inches of this FCC crystal? Three significant digits and fixed point notation.
Answer:
the lattice constant is 0.270 inches
Explanation:
Given the data in the question;
For FCC lattice;
a = b = c, ∝ = β = α = 90°
from the image below;
AC = 0.19 + 0.19/2 + 0.19/2 + 2(0.001) inch
AC = 0.19 + 0.095 + 0.095 + 0.002
AC = 0.382 inches
Now using Pythagoras theorem
AC² = AB² + BC²
since a = b = c
AC² = a² + a²
(0.382)² = 2a²
2a² = 0.145924
a² = 0.145924 / 2
a² = 0.072962
a = √0.072962
a = 0.27011 ≈ 0.270 inches
Therefore, the lattice constant is 0.270 inches
Hydrocarbons are compounds that are composed of only carbon and hydrogen atoms. A hydrocarbon has a density of 2.59 g/L at STP. What is the molar mass of this hydrocarbon? Be sure to include units with your answer.
Answer:
58.0 g/mol
Explanation:
At STP, one mole occupies 22.4 liters. One mole of the hydrocarbon would have a mass of ...
(2.59 g/L)(22.4 L/mol) ≈ 58.0 g/mol
Answer:
58.0 g/molthe molar mass of this given hydrocarbonConsider the following elementary reaction:
2NO(g) → N2O2(g)
Suppose we let k1 stand for the rate constant for this reaction, and k-1 stand for the rate constant of the reverse reaction. Write the expression that gives the equilibrium concentration of NO in terms of k1, k-1. And the equilibrium concentration of N2O2.
Answer:
[tex][NO]=\frac{k_{-1}}{k_1} [N_2O_2][/tex]
Explanation:
Hello!
In this case, since the reaction may be assumed in chemical equilibrium, we can write up the rate law as shown below:
[tex]r=-k_1[NO]+k_{-1}[N_2O_2][/tex]
However, since the rate of reaction at equilibrium is zero, due to the fact that the concentrations remains the same, we can write:
[tex]0=-k_1[NO]+k_{-1}[N_2O_2][/tex]
Which can be also written as:
[tex]k_1[NO]=k_{-1}[N_2O_2][/tex]
Then, we solve for the concentration of NO to obtain:
[tex][NO]=\frac{k_{-1}}{k_1} [N_2O_2][/tex]
Best regards!
24. The vaporization point of water is the same as its condensation point. True or False?
a. True
b. False
Answer:
pretty sure it's false
Explanation:
Witch regard to the ph scale, a solution with a ph . A. Lower than 7 is considered basic
Answer:
false
Explanation:
if it is lower than 7 It is acid