Answer:
c. Looking for improvements
Explanation:
I took the quiz and it was right
Answer: C
Explanation:
just took the test
Calculate the number of phosphorus atoms in 6.2g of phosphorus
Answer:
9.33 e22
Explanation:
For moles
N=m/M
N=6.2/40
N=0.155
For total no. Of atoms:
Atoms= N × 6.02e23
Atoms= 0.155× 6.02e23
Atoms= 9.33e22
What is one characteristic that makes Earth capable of supporting life?
A. It has ocean currents that circulate water from pole to pole.
O B. It has a strong magnetic field that protects organisms from
harmful radiation.
C. It is in a solar system located in one of the outer arms of a spiral
galaxy
D. It has more mass than any of the other planets of the inner solar
system.
Answer:
it is option (d)
it has more mass than any of the other planets of the inner solar system
 Help ASAP only right answers only no spam don’t answer if you don’t know
…..
Answer:
Inference
Explanation:
I mean, it's not difficult.
A theory is an unproven explanation.
An inference is a guess/educated guess where you don't have all the facts.
For example, if "Bob" is caught in the kitchen with a ketchup stain on his shirt, you are inferencing that he used the ketchup.
However, if you see a ketchup bottle nearby or saw it earlier, then it is not, because you already have the facts that ketchup was used.
Aluminum hydroxide, with heat, creates__
Which of the following
Combination,decomposition,
Single replacement,
Double replacement,
Combustion
Answer: Decomposition is the answer
Explanation: why because aluminium hydroxide would decomposes in the presence of heat and would form an oxide which is aluminium oxide and would also form water as a product.
HOPE THIS HELPS!!
CH4 (g) + O2 (g) → CO2 (g) + H2O (g) to. If 28.6 g of CH4 is reacted with 57.6 g of O2, calculate the number of grams of CO2 produced. b. If you actually get 32.1 g of CO2, calculate the percent yield. c. Calculate the number of moles of excess reagent remaining at the end of the reaction.
Answer:
See explanation
Explanation:
First we must obtain the limiting reactant. The equation of the reaction is;
CH4 (g) + 2O2 (g) → CO2 (g) + 2H2O (g)
Number of moles of CH4= 28.6 g/16g/mol = 1.8 moles
Since the reaction is 1:1, 1.8 moles of CO2 was produced
Number of moles of O2 = 57.6 g/32 g/mol = 1.8 moles
2 moles of O2 produced 1 mole of CO2
1.8 moles of O2 produced 1.8 × 1/2 = 0.9 moles of CO2
Hence O2 is the limiting reactant
Mass of CO2 produced = 0.9 moles × 44 g/mol = 39.6 g
%yield = 32.1g/39.6 g × 100
%yield = 81.1%
According to the reaction equation;
2moles of O2 reacts with 1 mole of CH4
1.8 moles of O2 reacts with 1.8 × 1/2 =0.9 moles of CH4
Number of moles of CH4 left = 1.8 moles - 0.9 moles
Number of moles of CH4 left = 0.9 moles
what is the application of chemistry
Answer:
Chemistry plays an important and useful role towards the development and growth of a number of industries. This includes industries like glass, cement, paper, textile, leather, dye etc. We also see huge applications of chemistry in industries like paints, pigments, petroleum, sugar, plastics, Pharmaceuticals.
What mass of barium sulfate (233 g/mol) is produced when 125 mL of a 0.150 M solution of barium chloride is mixed with 125 mL of a 0.150 M solution of iron(III) sulfate
Answer:
4.37 g of barium sulphate
Explanation:
The reaction equation is;
3BaCl2(aq) + Fe2(SO4)3(aq) ---->3 BaSO4(s) + 2FeCl3(aq)
From the question, the number of moles of both barium chloride and FeSO4 = 125/1000 L × 0.150 M = 0.01875 moles
To find the limiting reactant;
3 moles of barium chloride yields 3 moles of barium sulphate
0.01875 moles of barium chloride yields 3 × 0.01875 moles/3 = 0.01875 moles of barium sulphate
1 mole of iron III sulphate yields 3 moles of barium sulphate
0.01875 molesof iron III sulphate yields 0.01875 moles ×3/1 = 0.05625 moles of barium sulphate
Hence,barium chloride is the limiting reactant
Amount of barium sulphate produced = 0.01875 moles × 233 g/mol = 4.37 g of barium sulphate
Select from below all elements that follow the DUET rule (not the octet rule). (you can select multiple)
a) Li
b) Mg
c) O
d)He
e) H
f) Ne
What are two factors that determine the concentration of hydronium (or hydroxide) ions in an acid (or base) solution?
Answer:
hydronium and hydroxide ions are present both in pure water and in all aqueous solutions, and their concentrations are inversely proportional as determined by the ion product of water (Kw). The concentrations of these ions in a solution are often critical determinants of the solution’s properties and the chemical behaviors of its other solutes, and specific vocabulary has been developed to describe these concentrations in relative terms. A solution is neutral if it contains equal concentrations of hydronium and hydroxide ions; acidic if it contains a greater concentration of hydronium ions than hydroxide ions; and basic if it contains a lesser concentration of hydronium ions than hydroxide ions.
Answer:
hydronium and hydroxide ions are present both in pure water and in all aqueous solutions, and their concentrations are inversely proportional as determined by the ion product of water
Explanation:
Not my work! I hope this helps!
14. Which of the following alkanols on oxidation is most likely to yield the
compound below?
CHICHICOOON
.CO
(A) Butanol (B) Propan-2-ol(2-methylbutan-1-ol (D) 2-methylpropan-1-
ol (E) 2-methylpropan-2-ol.
Answer:
A
Explanation:
I think that is the ans but am not sure
Answer:
2-methylpropan-1-ol.
Explanation:
[tex]{ \tt{CH _{3}CH(CH _{3})CH _{2}OH}}[/tex]
The table shows the charge on three unknown subatomic particles.
X positive
Y no charge
Z negative
Which particle is most likely present in the space outside of the nucleus of the atom?
Answer:
Z negative
Explanation:
The negative charge shows that this is an electron. Electrons are present outside the nucleus of the atom and having negative charge. Usually represented by e-
Answer:
Only Z?
Explanation:
Why are most plants green out of all the colors?
Answer: Different forms of chlorophyll
Explanation:
Depending on the significance the of the chlorophyll it’s function is to absorb light, which excites electrons in the chlorophyll.
Answer:
Plant cells have an organelle called chloroplast in them. Chloroplast contains a green pigment called chlorophyll which gives plants it's green color.
Chlorophyll is important in plants as it helps the plant in producing food with the process of photosynthesis.
please provide is matter about us pure all NCERT questions and answers
Answer:
I hope that's what u were lookong for :))
Explanation:
give me a fully balanced equation of lead monoxide and nitric acid
Answer:
Explanation:
Lead Monoxide: PbO
Nitric Acid: HNO3
PbO + 2 HNO3 ---> Pb(NO3)2 + H2O
Answer:
Explanation:
mono mean single so lead monoxide is PbO
nitric acid is HNO3
both Pb n O are double-charged while H n NO3 are single
so balanced eqn is:
PbO + 2HNO3 -> Pb(NO3)2 + H2O
Blood tests can be used to check a person's blood glucose and hormone levels. The tabular column given below shows the result of two blood tests carried out on three people to check their blood glucose levels. Person 1 is healthy
Answer:
In after fasting test, Person 2 has slightly higher blood glucose level than person 1.
In after drinking glucose test, Person 3 has much high glucose level than person 1.
Explanation:
Blood sugar test determines the level of glucose present in body. The test can be taken after intake of food / glucose or after fasting for 12 hours. Results of both tests are compared to identify level of glucose present in human body. In after fasting test person has higher glucose and in another test person 3 has higher glucose level.
The first excited state of a particular atom in a gas is 6.1 eV above the ground state. A moving electron collides with one of these atoms, and excites the atom to its first excited state. Immediately after the collision the kinetic energy of the electron is 3.2 eV. What was the kinetic energy of the electron just before the collision
Answer:
The kinetic energy of the electron just before the collision is 9.3 eV.
Explanation:
We can find the kinetic energy of the electron before the collision can be found by energy conservation:
[tex] E_{i} = E_{f} [/tex]
[tex] K_{a_{i}} + K_{e_{i}} = K_{a_{f}} + K_{e_{f}} [/tex] (1)
Where:
[tex]K_{a_{i}}[/tex]: is the initial kinetic energy of the atom
[tex]K_{a_{f}}[/tex]: is the final kinetic energy of the atom = 6.1 eV + [tex]K_{a_{i}}[/tex]
[tex]K_{e_{i}}[/tex]: is the initial kinetic energy of the electron =?
[tex]K_{e_{f}}[/tex]: is the final kinetic energy of the electron = 3.2 eV
By solving equation (1) for [tex]K_{e_{i}}[/tex] we have:
[tex]K_{a_{i}} + K_{e_{i}} = (6.1 eV + K_{a_{i}}) + 3.2 eV[/tex]
[tex] K_{e_{i}} = 6.1 eV + 3.2 eV = 9.3 eV [/tex]
Therefore, the kinetic energy of the electron just before the collision is 9.3 eV.
I hope it helps you!
The laboratory test of a patient shows blood calcium level of 8.8meq/l. How many moles of calcium ions are in 0.50l of blood?
Answer:
2.2 × 10⁻³ mol
Explanation:
Step 1: Calculate the number of equivalents in 0.50 L of blood
The blood calcium level of 8.8 meq/L.
0.50 L Blood × 8.8 meq/L = 4.4 meq = 4.4 × 10⁻³ eq
Step 2: Calculate the number of moles of calcium
Calcium has a charge of 2. Thus, it has 2 equivalents per mole.
4.4 × 10⁻³ eq × 1 mol/2 eq = 2.2 × 10⁻³ mol
Which of these is an example of a chemical change?
Answer:
D. Burning a peice of wood
Explanation:
Because when you burn wood a chemical reaction happenes between the flames and the wood making the wood into ashes.
Hope this helps you :)
The dissolving salt in water is an an example of a chemical change. The correct option is A.
A chemical change, also known as a chemical reaction, is the production of new substances with changing chemical compositions and characteristics.
In water, sodium chloride dissociates into Na+ ions and Cl- ions, which may be described as a chemical process.
The ionic connections between the atoms are broken as salt dissolves. Because the reactant (sodium chloride or NaCl) varies from the products (sodium and chloride ions), a chemical reaction takes place.
Thus, the correct option is A.
For more details regarding chemical change, visit:
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need help really quickly!!
so how do you predict products when only reactants are given?
i can do everything else that’s asked for the hw but i don’t know how to do this one.
the first pair of reactants is calcium hydroxide + ammonium chloride.
Answer: so in this question are reactants are calcium hydroxide and ammonium chloride
Explanation: first of all know that a salt would be formed so here the salts present are calcium and chloride so they would react to form the salt calcium chloride, then since ammonium ions are present ammonia gas would be formed then, hydroxide ions (OH) are also present so water would be formed so our final products would be calcium chloride , ammonia and water .
WORD EQUATION
calcium hydroxide+ ammonium chloride⇒ calcium chloride+ ammonia+ water
CHEMICAL EQUATION
CA(OH)2+2NH4CL⇒ CACL2+2NH3+2H2O
Which general equation shows a double-displacement reaction?
O A. AB + CD + AC + BD
O B. AB → A+B
O C. AB + CD → AD + CB
O D. A+B → AB
Answer:
O A. AB + CD + AC + BD
explanation:
Explanation:
A.ab+cd+ac+bd is your answer
Which redox reaction would most likely occur if silver and zinc metal were added to a solution that contained silver and zinc ions?
Answer:
D. Zn²⁺ + 2Ag → Zn + 2Ag⁺
Explanation:
On the reduction potential chart, we have that silver ion Ag⁺ is a stronger oxidizing agent than, zinc, Zn, which is a reducing reducing agent the compared to silver
Therefore, the redox reaction that will occur is that the zinc, Zn, will be oxidized to Zn²⁺ ion, while the silver, Ag²⁺ ion will be reduced to silver deposits Ag, therefore, the zinc will displace the silver in the solution containing silver and zinc ions because zinc is higher than silver in the reactivity series
The reduction potential Zn → Zn²⁺ + 2e⁻ = +0.76
The reduction potential for Ag⁺ + e⁻ → Ag = +0.8
Therefore, given that redox reactions are reversible, we get the following likely redux reaction;
Zn(s) + 2Ag⁺(aq) ⇄ 2Ag(s) + Zn²⁺(aq)
Therefore, from the given options;
Zn²⁺(aq) + 2Ag(s) → Zn(s) + 2Ag⁺(aq) is the reaction most likely to occur.
Which of the following happens during an endothermic chemical change?
Heat is absorbed.
Heat is released.
Net energy decreases.
Net energy remains constant.
Answer:
Heat is absorbed.
Explanation:
Endothermic reactions: Heat is absorbed.
When there is a change in the endothermic chemical so here heat is absorbed.
What are Endothermic reactions?It is the type of the chemical reaction that absorbed the heat from the environment. The absorbed energy that gives the activation energy for the reaction to arise.
hence, When there is a change in the endothermic chemical so here heat is absorbed.
Therefore, the first option is correct.
Learn more about heat here: https://brainly.com/question/1488118
(d) (i) How can the water molecules from the iceberg end up as water in the lake?
Explanation:
If the iceberg is near the lake and the water molecules melt, then the molecules will slide down. The iceberg could be melting for many reasons - it can be purposely destroyed, the sun could be melting it, or it might naturally fall in. So, this is the answer to your question. Hope it helps!
use a periodic table to write the electron configuration of selenium
Answer: The electronic configuration of selenium is [tex]1s^22s^22p^63s^23p^64s^23d^{10}4p^4[/tex]
Explanation:
The atomic number is defined as the number of protons or number of electrons present in a neutral atom.
Number of electrons will be equal to the atomic number of an atom.
Electronic configuration is defined as the representation of electrons in an atom.
Selenium is the 34th element of the periodic table.
The electronic configuration of Selenium is [tex]1s^22s^22p^63s^23p^64s^23d^{10}4p^4[/tex]
It has 6 electrons that are present in the outermost shell.
how many distinct monochlorinated products can result when methylcyclohexane is subjected to free radical chlorination under UV light
Answer:
How many distinct monochlorinated products can result when methylcyclohexane is subjected to free radical chlorination under UV light.
Explanation:
Consider 1-methylcyclohexane:
Its structure is shown below:
It has primary [tex]1^o[/tex], secondary [tex]2^o[/tex]and tertiary [tex]3^o[/tex] carbons as shown in the image.
So, the following mono chlorinated product will be formed.
True or false, Henry Moseley discovered through X-Ray crystallography the number of neutrons that were present
in the nucleus of atoms of every element.
Answer:
Im pretty sure its true
Explanation:
Answer:
answer is true .
Explanation:
this may help you
What are the steps for writing the formula for an ionic compound? Naming an ionic compound?
Answer:
i hope it will help you
Explanation:
To find the formula of an ionic compound, first identify the cation and write down its symbol and charge. Then, identify the anion and write down its symbol and charge. Finally, combine the two ions to form an electrically neutral compound.
How is the relation between the volume and temperature? Explain.
Methane is the main component of natural gas. Using the given reaction enthalpy, calculate the heat energy produced by the combustion of one kilogram of methane.
Answer: The heat energy produced is 53831.25KJ
Explanation:
METHANE is the main component of natural gas. It can undergo combustion reaction in air with a bright blue flame to produce carbondioxide and water. The heat of reaction (enthalpy) is negative because heat is absorbed during the chemical reaction. To calculate the heat energy produced by the combustion of one kilogram (1 kg) of methane the following steps are taken:
Molecular mass of methane =16 gm/mol.
So moles of 1 kg methane =
Given mass of methane ÷ molecular weight of methane
But the given mass = 1kg = 1000g
Therefore,
moles of 1000g methane = 1000÷16
= 62.5 moles
Hence, energy evolved = (moles of methane) × (heat of combustion)
Therefore,
heat energy produced= 62.5 × (-861.3kj)
= -53831.25kj
The heat energy produced by the combustion of one kilogram of methane is –53831.25 KJ
We'll begin by calculating the number of mole in 1 Kg of CH₄
Mass of CH₄ = 1 kg = 1000 g
Molar mass of CH₄ = 12 + (4×1) = 16 g/mol
Mole of CH₄ =?Mole = mass /molar mass
Mole of CH₄ = 1000 / 16
Mole = 62.5 moles Finally, we shall determine the heat energy produced from the reaction.CH₄ + 2O₂ —> CO₂ + 2H₂O ΔH = –861.3 KJ
From the balanced equation above,
1 mole of CH₄ reacted to produce –861.3 KJ.
Therefore,
62.5 moles of CH₄ will react to produce = 62.5 × –861.3 = –53831.25 KJ
Thus, –53831.25 KJ of heat energy is produced.
Complete Question is located in the attached photo
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Which of the following statements about the nucleus is false?
A. Contains nearly all of the mass of the atom.
B. Able to be lost or gained in chemical reactions.
C. None of these
D. Made up of protons and neutrons
Answer:
B. Able to be lost or gained in chemical reactions.
Answer:
B
Explanation:
a chemical reaction would only move the nucleas