9) What is the density of the gold rock with a mass of 386 grams and has a volume of 20 cubic centimeters?
O 0.193 g/cc
O 193 g/cc
O 1.93 g/cc
19.3 g/cc
Answer:
density= mass/volume
hence density of gold rock
= 386/20
=19.3 g/cc
In an exothermic the change in enthalpy is usually
Positive, because the potential energy of the reactants is higher than the potential energy of the products
Neutral, because the potential energy of the products and reactants cancel each other out.
Negative, because the potential energy of the reactants is higher than the potential energy of the products
Positive, because the potential energy of the reactants is lower than the potential energy of the products
Answer:
Negative, because the potential energy of the reactants is higher than the potential energy of the products
Explanation:
Exothermic reaction is a reaction in which heat is released to surrounding. This is due to the fact that the heat content of the reactant is higher than the heat content of product thus producing a negative enthalpy change (ΔH) i.e
Enthalpy change = Heat of product – Heat of reactant
ΔH = Hp – Hr = negative
Considering the options given in the question above, the correct answer is:
Negative, because the potential energy of the reactants is higher than the potential energy of the products
DUE TONIGHT!
I need help doing this question and please type an ACTUAL answer. I don’t want none of that “aNsWeR iN FiLe”. Thank you!
Calculate the specific heat (Cp) for indium metal given a 1.0 mole absorbs 53.0 J
while increasing in temperature from 297.5K to 299.5K.
Answer:
27J/Kmol
Explanation:
Heat = number of moles times the Moeller heat capacity chimes the change in temperature.
^ Q = nC△T
^ C = Q/ n△T = +53J / (1mol) (299.5K - 297.5K)
^ = 26.5 (rounded to 27)
Most of the matter making up the earth is composed of
A. gases
B. compounds
C. mixtures
Most of the matter making up earth is composed of compounds. I think
How
many
moles of water are produced from 12.8 moles of oxygen?
with work
Answer:
12.8 moles
Explanation:
The formula for water is H2O, so for every mole of water, there are two moles of hydrogen and one mole of oxygen.
As the ratio of oxygen particles to water particles is one to one, 12.8 moles of oxygen are required to produce 12.8 moles of water.
Therefore, 12.8 moles of water are produced from 12.8 moles of oxygen (assuming hydrogen is available in excess).
What is the main way energy from the Sun moves around Earth?
O
O A.
From the atmosphere
O
B.
From human energy
O
C.
From the ocean currents
Answer:
All of the energy from the Sun that reaches the Earth arrives as solar radiation, part of a large collection of energy called the electromagnetic radiation spectrum. Solar radiation includes visible light, ultraviolet light, infrared, radio waves, X-rays, and gamma rays. Radiation is one way to transfer heat.
How to know the state of elements in a reaction
Answer:
each compound or molecule is indicated in subscript next to the compound by an abbreviation in parentheses. For example, a compound in the gas state would be indicated by (g), solid (s), liquid (l), and aqueous (aq).
Explanation:
Commercially available concentrated hydrochloric acid is 37.0% w/w HCl. Its density is 1.18g/ml. Calculate the molarity of concentrated HCl?
Answer:
M = 12.0M
Explanation:
Hello there!
In this case, according to the given by-mass percent of HCl, which can be set up in terms of mass of HCl over mass of solution, we can calculate the molarity, by multiplying by the density to get the mL's of solution and further convert to liters. Moreover, the molar mass of HCl (36.46 g/mol) must be also used to calculate the moles, since molar units requires moles of solute and liters of solution as shown below:
[tex]M=\frac{37.0gHCl}{100g\ sln}*\frac{1.18g\ sln}{1mL\ sln}*\frac{1000mL\ sln}{1L \ sln}*\frac{1molHCl}{36.46gHCl}\\\\M= 12.0M[/tex]
Best regards!
Mr. Whiteman has two stock solutions of sulfuric acid (H2SO4) in the supply closet: 12.1 M and 6.0 M. If he wants to make 10.0 mL of a 1.0 M solution, which stock solution makes more sense to use? Justify with two calculations.
Answer:
12.1-M requires less volume of stock solution.
Explanation:
Hello there!
In this case, according to the foundations of dilution processes, it turns out convenient to remember that the moles of the solute before and after the dilution remains the same; for that reason we use the following equation:
[tex]M_1V_1=M_2V_2[/tex]
Relating the initial and final molarities and volumes. Now, it is seen that V2 is 10.0 mL and M2 is 1.0 M, which means that if we solve for V1 for 12.1 M and 6.0 M, we obtain the following volumes:
[tex]V_1=\frac{M_2V_2}{M_1} \\\\V_1^{12.1M}=\frac{1.0M*10.0 mL}{12.1M}=0.826mL\\\\V_1^{6.0M}=\frac{1.0M*10.0 mL}{6.0M}=1.67mL[/tex]
Therefore, since the 12.1-M solution requires less volume of stock solution, it makes sense to use this one as the initial solution.
Best regards!
A 25°C sample of gas has a volume of 5.0 L. What will it’s volume be if it is heated to 50.0°C?
What is the pH at the equivalence point in the titration of 10.0 mL of 0.39 M HZ with 0.200 M NaOH? Ka = 2.4 × 10−6 for HZ.
Answer:
pH = 9.37
Explanation:
The reaction of HZ with NaOH occurs as follows:
HZ + NaOH → H₂O + Na⁺ + Z⁻
When the reaction is in the equivalence point, the moles added of HZ = Moles of NaOH.
At equivalence point, you will have in solution just NaZ that is in equilibrium with water as follows:
Z⁻(aq) + H₂O(l) ⇄ OH⁻(aq) + HZ(aq)
Where K of equilibrium is Kw / Ka = 1x10⁻¹⁴ / 2.4x10⁻⁶ = 4.17x10⁻⁹
And K is defined as:
K = 4.17x10⁻⁹ = [OH⁻] [HZ] / [Z⁻]
To solve this question we must find [Z⁻] and as [OH⁻] and [HZ] comes from the same equilibrium, both are equal and we can find [OH⁻] in order to solve pH:
Moles NaOH added = Moles HZ:
0.010L * (0.39mol / L) = 3.9x10⁻³ moles HZ = Moles NaOH added
The volume of 0.200M NaOH must be:
3.9x10⁻³ moles * (1L / 0.200moles) = 0.0195L.
The moles of HZ = Moles Z⁻ after the reaction and the volume is 0.010L + 0.0195L = 0.0295L. Thus, [Z⁻] is:
[Z⁻] = 3.9x10⁻³ moles / 0.0295L
[Z⁻] = 0.132M
Replacing in K expression:
4.17x10⁻⁹ = [OH⁻] [HZ] / [Z⁻]
4.17x10⁻⁹ = [X] [X] / [0.132]
5.51x10⁻¹⁰ = X²
X = 2.35x10⁻⁵M = [OH⁻]
As pOH = -log [OH⁻]
pOH = 4.63
And pH is
pH = 14 -pOH
pH = 9.37On a hot day, a student places a glass of cold lemonade on a table outdoors. After a few minutes, water droplets have formed on the outside of the glass.
Is energy absorbed or released by the cold lemonade? Explain your answer.
Compare average kinetic energy for the air molecules and lemonade molecules when the student first places the lemonade outdoors. Explain your answer.
Explain how and why the water droplets form on the outside of the glass.
Answer:
ye but sdfajkd tryng to play me
Explanation:
Answer:
Vapor is released out of the lemonade because when you place it in a hot it will increase.
Explanation:
Nitrous acid is classified as an Arrhenius acid because HNO2 contains
1. OH-ions
2. 02-ions
3. NO2-ions
4. H+ ions
4) H+ions is your answer , good morning , have a great day ahead.
what are the chemical symbols of the particles found in the calcium chloride crystal (lattice)
Answer:
Formula and structure: The chemical formula of calcium chloride is CaCl2, and its molar mass is 110.983 g/mol. It is an ionic compound consisting of the calcium cation (Ca2+) and two chlorine anions (Cl-). The bivalent calcium metal forms an ionic bond with two chlorine atoms, as shown below.
Based on the ionic nature of calcium chloride, the chemical symbols of the particles found in the calcium chloride crystal is Ca²⁺ and Cl⁻.
What are ionic compounds?
Ionic compounds are compounds which are composed of ions.
Calcium chloride is an ionic compound composed of the ions, calcium ions and chloride ions.
The chemical formula of calcium chloride is CaCl2, and its molar mass is 110.983 g/mol.
The symbol for calcium ion is Ca²⁺
The symbol for chloride ion is Cl⁻.
Therefore, the chemical symbols of the particles found in the calcium chloride crystal is Ca²⁺ and Cl⁻.
Learn more about ionic compounds at: https://brainly.com/question/11638999
Which reaction occurs when equivalent quantities of H" (or H30) and OH" are mixed?
1.
oxidation
2.
reduction
3
hydrolysis
4.
neutralization
Answer: A reaction which occurs when equivalent quantities of H" (or [tex]H_{3}O^{+}[/tex]) and OH" are mixed is a neutralization reaction.
Explanation:
When acid and base chemically combine together to form sat and water then it is know as neutralization reaction.
An acidic substance gives hydrogen ions [tex](H^{+})[/tex] on dissociation and a basic substance gives hydroxide ions [tex](OH^{-})[/tex] on dissociation.
For example, [tex]H^{+} + OH^{-} \rightarrow H_{2}O[/tex] is a neutralization reaction where an acid and base are mixed together to form water.
No salt is formed as because here the reactants are not present as compounds.
In a hydrolysis reaction, water molecule(s) is added to the reactant molecules.
For example, [tex]CH_{3}COOCH_{3} + H_2O \rightarrow CH_{3}COOH + CH_{3}OH[/tex]
Oxidation is the process of addition of oxygen to a molecule and removal of hydrogen.
Reduction is the process of addition of hydrogen in a compound and the removal of oxygen atom.
Therefore, we can conclude that reaction which occurs when equivalent quantities of H" (or [tex]H_{3}O^{+}[/tex]) and OH" are mixed is a neutralization reaction.
Calcium carbonate + hydrochloric acid forms copper ___ + water + carbon dioxide
What does it form copper what please help me
Answer:
The answer copper carbonate
Combustion engines became common in the mid-1800s when people began to use them to power ships, trains, and
machinery in factories. Combustion engines add carbon dioxide to the air, and as a result, carbon dioxide in the
atmosphere increased quickly. How did this change the total amount of energy in the Earth system, and how did this
change happen? How did this affect global average temperature?
I need help please and don’t send the fake link): < just to get points
Answer:
The correct answer is - increased the global average temperature.
Explanation:
Combustion is the process that increases the carbon dioxide in the atmosphere, which results in entering more energy into the Earth system than existed from it. Therefore, the amount of energy increased in the system of the earth or surface of the earth.
The reason behind it is that carbon dioxide trapped and redirects energy back toward the Earth's surface, which is absorbed by Earth's surface and surface increased, and global average temperature increased.
Combustion process increases the global average temperature of the earth by absorbing and emitting the energy revert back to earth.
What is combustion?Combustion is a process exothermic process in which organic molecules burns in the presence of oxygen to produce energy in the form of heat and light and CO₂ gas.
CO₂ gas is a green house gas which traps the energy of the atmosphere and revert back it into the earth surface, due to which temperature of the earth surface and atmosphere increases which results in the elevation of global average temperature.
Hence, combustion increases the global average temperature.
To know more about combustion, visit the below link:
https://brainly.com/question/15246277
What is the percent by mass concentration of 1000 ml of a solution (d=1.5 g/ml) that contains 50 g of solute in it?
Answer: The percent by mass concentration is 33.3 %
Explanation:
Mass percent is the ratio of mass of solute to the mass of solution in terms of percentage.
mass of solute = 50 g
mass of solution = [tex]{\text {density of solution}}\times {\text {volume of solution}}=1.5g/ml\times 1000ml=1500g[/tex]
Mass percentage = [tex]\frac{50g}{1500g}\times 100\%=33.3\%[/tex]
Thus percent by mass concentration of 1000 ml of a solution (d=1.5 g/ml) that contains 50 g of solute in it is 33.3 %
HELP !
The provided balanced equation applies to the reaction that takes place between lithium hydroxide and sulfuric acid. 2LiOH + H2SO4 -> Li2SO4 + 2H2O .
If the reaction begins with 26.7 grams of lithium hydroxide (LIOH) and 164.08 grams of suite acid (H2SO4.), how many grams of lithium sulfate (Li2SO4,) is produced? Assume 100% yield . Round your answer to the nearest tenth of a gram .
Answer:
60g or 61.28g
Explanation:
Trust me on this I had the same problem as you
What is the best common way to convert fossil fuels into energy?
a. oxidation
b. reaction
c. combustion
d. neutralization
You have 1 1/2 moles of 1 kg bottles of O2. What is the mass of O2 that you have?
A. 9.033x10^23 kg
B. 9.033x10^23 atoms
C. 1.80x10^27 kg
D. 1.806x10^24 moles
It is not B as I have already tried it :(
Answer:
A: 9.033 × 10^(23) kg
Explanation:
According to avogadro's number, we know that;
1 mole = 6.022 × 10^(23) kg
Thus;
1½(1.5) mole of O2 will produce;
(1.5 × 6.022 × 10^(23))/1 = 9.033 × 10^(23) kg
Looking at the options, the correct one is Option A.
In chemical reactions, the number of atoms in the product is ________________.
A. the same as the number of atoms in the reactants
B. less than the number of atoms in the reactants
C. greater than the number of atoms in the reactants
D. the same as the number of molecules in the reactants
Answer:
A
Explanation:
How does every single cell in the body get the substances it needs to carry out the chemical reaction that provides it energy?
what is the difference between isotopes and allotrope not more than three line
Answer:
An allotrope is one way that atoms can be arranged in a solid. An isotope is one way that protons and neutrons can form the same atomic element.
Science please help. I will add you and please don’t give me any random websites
Answer:
C
Explanation:
Answer:
D)
Explanation:
On land, volcanoes form when one tectonic plate moves under another. Usually a thin, heavy oceanic plate subducts, or moves under, a thicker continental plate. When this happens, the ocean plate sinks into the mantle.
what happen when a piece of silver metal is added to the copper sulphate solution
Answer:
Explanation:When silver Ag metal is added to copper sulphate CuSO4 solution, no reaction takes place as silver is less reactive than that of copper and cannot displace copper from its solution. Hence, when a piece of silver metal is added to copper sulphate solution there will be no reaction.
Answer:
There will be no reaction
Explanation:
Therefore, when silver Ag metal is added to copper sulphate CuSO4 solution, no reaction takes place as silver is less reactive than that of copper and cannot displace copper from its solution. Hence, when a piece of silver metal is added to copper sulphate solution there will be no reaction.
Why is it important for the daughter cells to divide a second time in meiosis?
The second division switches parts of matching chromatids to increase genetic variation.
The second division forms four identical cells to ensure that all offspring have the same
The second division sorts chromosomes into cells that are the same as the parent cells.
The second division forms haploid cells that can combine with other haploid cells during fertilization.
Answer:
The second division switches parts of matching chromatids to increase genetic variation.
Explanation:
Meiosis and fertilization create genetic variation by making new combinations of gene variants (alleles).
WHAT IS THE PH OF LEMON JUICE IF IT HAS A HYDROGEN ION CONCENTRATION [AT]ON[H^ + ]=5.0*10^ -2 M.
Can somebody help me please !!!!!!
Answer:
ph=2
Explanation:
In a solution, litmus is blue. The pH of the solution could be
1. 10
2. 2
3. 3
4. 4
Answer:
1. 10
Explanation
when litmus paper is blue that means the solution is basic and 10 on the pH scale is the most basic out of all your options
How is matter conserved through cellular respiration
Answer:
In cellular respiration, complex molecules containing carbon react with oxygen to produce carbon dioxide and other materials. ... Matter is conserved during cellular respiration because atoms are conserved in physical and chemical processes
Explanation:
I hope this helps