Answer:
Water has 18 grams per mole so 9 grams is 0.5 moles of water. There are 6.022* 10^23 molecules in a mole. Each water molecule contains one oxygen and two hydrogens.
is this right or wrong ? pls help rn
your answer is correct good luckk!!!:)
Why is it important to know which category of microorganism has caused an infection?
Select one:
a. Treatment depends on which kind of organism caused the infection.
b. Probiotic infections can actually worsen some conditions.
c. Some infections can indicate cancer.
d. Some types of infections are highly contagious.
PLEASE ANSWER QUICKLY
Answer:
A
Explanation:
How many minutes will it take to plate out 4.50 g of Cu from a solution of Cu(NO3)2 (aq) onto the cathode of an electrolytic cell when 8.00 A of current are used?
a. 28.5 min.b. 3.06 × 10^−9 min.c. 14.2 min.d. 1.82 × 10^3 min.
Answer:
a. 28.5 min
Explanation:
The computation of the number of minutes would it take to plate out is as follows:
Cu+2 +2e [tex]\rightarrow[/tex]Cu
The two moles of electrons could be generated for the copper i.e. deposited
Now
moles of copper is
= 4.5 ÷ 63.5
= 0.071
The 63.5 represents the atomic copper weight
Now mole of electrons deposited is
= 0.071 × 2
= 0.142
Now
quantitiy of electricity needed
= moles of electrons deposited × 96500
= 0.142 × 96500
= 13703 coulums
As per electricity quantity needed
= current × time(seconds)
= 13703 = 8 × t
t = 13703 ÷ 8
= 1713 seconds
= 1713 ÷ 60 minutes
=28.5 min
hence, the correct option is a.
how many moles is 8.72x10^24 atoms? can you solve the equation too?
Answer:
14.49 molesExplanation:
To find the number of moles in a substance given it's number of entities we use the formula
[tex]n = \frac{N}{L} \\[/tex]
where n is the number of moles
N is the number of entities
L is the Avogadro's constant which is
6.02 × 10²³ entities
From the question we have
[tex]n = \frac{8.72 \times {10}^{24} }{6.02 \times {10}^{23} } \\ = 14.48504...[/tex]
We have the final answer as
14.49 molesHope this helps you
Heat energy always moves in which direction?
Group of answer choices
Large objects to small objects
Dark objects to light objects
Warm objects to cool objects
Smooth objects to rough objects
Answer:
large object to small objects
Answer:
The answer is C or warm objects to cool objects
Explanation:
Heat is the thermal energy flows from one substance to another when the substances differ in temperature. When you drink hot chocolate the heat from the liquid will flow to your mouth.
Help with this question pleasee
Which is associated with low humidity? *
dry air
warm air
rainforest
coastal area
Answer:
A: dry air
Explanation:
Trust me this is right, I’m doing the exam rn and if its not right I will come back and edit this.
Answer:
guy above me is right
Explanation:
100% on quiz
please help this makes no sense to me!!
Answer:
potassium nitrate= KNO3 ---> KNO2 + O2 and a gas evolution reaction
Explanation:
i think
is 4 Fe + 3 O2 --> 2 Fe2O3
balanced?
Answer:
Yes the given equation is balanced.
Explanation:
Chemical equation:
Fe + O₂ → Fe₂O₃
Balanced chemical equation:
4Fe + 3O₂ → 2Fe₂O₃
There are four iron and six oxygen atoms on both side of equation thus the given equation is balanced.
The given reaction also follow the law of conservation of mass.
According to the law of conservation mass, mass can neither be created nor destroyed in a chemical equation.
This law was given by French chemist Antoine Lavoisier in 1789. According to this law mass of reactant and mass of product must be equal, because masses are not created or destroyed in a chemical reaction.
This reaction is synthesis reaction:
Synthesis reaction:
It is the reaction in which two or more simple substance react to give one or more complex product.
A + B → AB
Compare and contrast the mass of the object to the size of the object.
Rust has the same properties as iron
True
False
Answer:
false
Explanation:
Directions: Read the paragraph and identify the correct words that fit in the given sentences
inside the box. Write your answer in a separate sheet of paper.
Elements
non-metal
chemical process components
metal
more
properties
metalloids
properties
Compounds
one
chemical
are made up of
Elements and Compounds are all around us. (1)
utumn or atoms of the same kind. They are the simplest type of matter and cannot
be broken down into components. Each element is made entirely from (2)
type of atom. Each element is unique and no two elements have the same set of
(3)
Some are in the same state but they have (4)
properties.
Some elements are (5) like iron, gold and silver. Others are (6) like
Nitrogen, Oxygen and Ilydrogen. There are elements that are (7)
like
Boron. Silicon and Germanium.
(8)
are combination of (9)
or (10)
elements
like water which is a combination of Hydrogen and Oxygen; salt which is made
up of sodium and chlorine; and rusts formed when an iron reacts with oxygen.
Compounds can be broken down into it's (11) through a (12)
process and formed when two elements are combined together. It has unique
properties that are different from the properties of the elements that make them
Answer:
1. Elements
2. one
3. properties
4. Chemical
5. metal
6. non-metal
7. metalloids
8. Compounds
9. one
10. more
11. components
12. chemical process
Explanation:
In the given paragraph a brief about the difference between element and compound is given.
Elements are made up of the same type of atoms and each element is made up of one atom, that is they cannot be broken down into any other substance. Each element is different from each other due to its properties, though some have the same physical properties but are different in chemical properties. Elements can be classified as metals such as iron and silver, non-metals such as oxygen and hydrogen, and metalloids such as boron and silicon.
Compounds are a combination of one or more elements such as water and salt. Compounds can be easily broken down into components through a chemical process.
Hence, the correct answer is:
1. Elements
2. one
3. properties
4. Chemical
5. metal
6. non-metal
7. metalloids
8. Compounds
9. one
10. more
11. components
12. chemical process
Which type of reaction is NaCl + AgNO3 → NaNO3 + AgCl?
synthesis
decomposition
oxidation
replacement
Answer:
replacement
Explanation:
The percent by mass of Ca in CaCl2 is equal to
1. (40/111) x 100
2. (111/40) x 100
3. (3/1) x 100
4. (1/3) x 100
Answer:
(40/111)×100Here is a bonus Answer✍️✍️Percent composition by elementElement Symbol Mass PercentChlorine Cl 63.888%Calcium Ca 36.112Mass percentage does not have any unit as numerator and denominator contains the same unit. The percent by mass of Ca in CaCl[tex]_2[/tex] is equal to (40/111) x 100. The correct option is option A.
What is percentage by mass?Mass percentage represents the the percentage of each element that is making a particular compound.
Mathematically,
Percentage of mass = (component’s mass ÷ total mass) x 100%
Atomic weight of different element of calcium chloride{ CaCl[tex]_2[/tex]} are
Ca = 40 ; Cl = 35
Total mass of Calcium element in calcium chloride = 40g/mol
Total mass of Chlorine atom in calcium chloride = 35× 2= 71g/mol
Total molar mass of calcium phosphate = 40 +71= 111g/mole
Percentage of calcium in calcium chloride =40÷111 = 36%
Therefore, the percent by mass of Ca in CaCl2 is equal to (40/111) x 100. The correct option is option A.
To learn more about mass percentage, here:
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The reaction of HCl with NaOH is represented by the equation
HCl(aq) + NaOH(aq) → NaCl(aq) + H2O(l)
What volume of 0.417 M HCl is required to titrate 11.9 mL of 0.151 M NaOH?
a. 4.3 mL
b. 2.39 mL
c. 0.749 mL
d. 32.8 mL
e. 11.9 mL
Answer:
a. 4.3 mL
Explanation:
Step 1: Write the balanced neutralization reaction
HCl(aq) + NaOH(aq) → NaCl(aq) + H₂O(l)
Step 2: Calculate the reacting moles of NaOH
11.9 mL of 0.151 M NaOH react.
0.0119 L × 0.151 mol/L = 0.00180 mol
Step 3: Calculate the reacting moles of HCl
The molar ratio of HCl to NaOH is 1:1. The reacting moles of HCl are 1/1 × 0.00180 mol = 0.00180 mol.
Step 4: Calculate the volume of 0.417 M HCl that contains 0.00180 moles of HCl
0.00180 mol × (1000 mL/0.417 mol) = 4.3 mL
According to the question,
Mass,
[tex]M_1 = 0.417[/tex][tex]M_2 = 11.9[/tex]Volume,
[tex]V_1 = ?[/tex][tex]V_2 = 0.151[/tex]As we know the relation,
→ [tex]M_1V_1 = M_2 V_2[/tex]
or,
→ [tex]V_1 = \frac{M_2 V_2}{M_1}[/tex]
By substituting the values, we get
[tex]= \frac{11.9\times 0.151}{0.417}[/tex]
[tex]= \frac{1.7969}{0.417}[/tex]
[tex]= 4.3 \ mL[/tex]
Thus the above answer is right.
Learn more about reaction here:
https://brainly.com/question/12205810
why is it important to know the number of valence electrons in an atom?
Answer:
Valence electrons are the electrons in the outermost energy level of an atom — in the energy level that is farthest away from the nucleus. Being able to determine the number of valence electrons in a particular atom gives you a big clue as to how that atom will react.
Explanation:
35. Which subatomic particle has almost no mass relative to the others: the proton, the neutron or the electron?
Answer:
electron
Explanation:
it has very little mass
Describe a chemical property of iron that you observed.
Answer:
Iron can rust in damp conditions. Or, it can dissolve readily in dilute acids.
Explanation:
Iron(III) nitrate + potassium sulfide product names
Which of these elements does not bond with other elements to form molecules?
Group of answer choices
Neon
Sulfur
Oxygen
Chlorine
Answer:
Explanation:b
Zuzana tests a common household substance and finds that it has a pH of 3.
What type of substance is in the scenario?
acidic
basic
salt
neutral
pH is a measurement of amount of hydronium ion H₃O⁺ in a given sample. More the value of hydronium ion concentration, more will be the solution acidic. The given substance is acidic. The correct option is option A.
What are acid and base?Acid is a solution which releases H⁺ hydrogen ion when dissolved in water. Base are the solution which releases hydroxide ion OH⁻ ion when dissolved in water. The pH of acid is between 0-7 on pH scale while for base pH range is from 7-14.
On subtracting pH from 14, we get pOH which measures the concentration of hydroxide ion in a given solution. pH depend on the temperature. At room temperature pH scale is between 0 to 14. pH of neutral solution is 7.
Therefore, the given substance is acidic. The correct option is option A.
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A. What is the frequency of light that has a wavelength of 6.2 x 10^-7 m?
B. Identify the color of this light.
C. Calculate the amount of energy given off by this atom.
Answer:
I think the answer is letter C
Which of the following best defines an allotrope?
Question 1 options:
Crystalline forms
Carbon atoms
Different forms of the same element
Similar bonding arrangements between atoms
Answer:
hi buddy!! here is ur ans: carbon atoms
How do atoms form chemical bonds
Answer:
Atoms form chemical bonds to achieve a full outer energy level, which is the most stable arrangement of electrons. A chemical bond is a force of attraction between atoms or ions. Bonds form when atoms share or transfer valence electrons. In a covalent bond, two atoms share one or more electrons.
In the case of a rigid rorator, i.e. two masses M1 and M2 placed on a rigid weightless rod, we start from the Schrodinger equation for two particles 1 and 2, and then we separate the movement of the center of masses. Give the formulas of both masses that we get as part of this procedure. Calculate these masses in atomic mass units for the HD molecule by approximating the masses H and D with their mass numbers.
Answer:
Masses in atomic mass units for the HD molecule by approximating the masses H and D with their mass numbers is explained below in complete detail.
Explanation:
Two volumes M1 and M2 are located on a rigid weightless rod in a rigid rotor position. Energy in a rigid rotator example: E = BJ(J+1) where, B = h/8pi2Ic, B is rotational regular, I is moment of inertia = ur2 where u is decreased mass = m1m2/m1+m2.
FOR HD MOLECULE: mass, u = mass of H*mass of D/mass of H + D. Atomic mass unit =1.67*10^-27 kg. So, u = 1*1.67*10-24 * 2*1.67*10-24 / 1.67*10-24+2*1.67*10-24 = 1.67*10-24*2/3 = 1.11*10-24 g.
Question 5
2 pts
To determine the density of an irregularly shaped object, a student immersed the object in 32.2 mL of water in a graduated cylinder, causing the level of the water to rise to 37.8 ml. If the object had a mass of 12.4 g, what is the density of the object?
O 0.32 g/mL
O 1.4 g/mL
O 3.4 g/mL
O 2.2 g/mL
Help quick right answer gets brainliest !!
Answer:
Explanation:
2.2 g/mL is the answer.
Why are standard electrode potentials usually measured at 1.0 M electrolyte concentration?
Answer:
To avoid variation due to concentration
Explanation:
Hope this helps :)
At room temperature, one of the molecules is a gas and one is a liquid. Identify which structure is a gas and which is a liquid.
bonds. Carbon dioxide has a. Ionic b. Covalent c. Nonpolar covalent d. Polar covalent
Answer:
B
Explanation:
Covalent bond.
To fight a bacterial infection, a patient was given an antibiotic to take for 10 days.
After the patient finished taking the antibiotics as directed, almost all the bacteria
were killed. After another 10 days, the patient was sick again with the same type of
infection. What most likely happened?
A. A few bacteria survived the antibiotics and stopped reproducing
B. Some bacteria were resistant to the antibiotic,and they reproduced
C. The antibiotic slowed the life cycle of the bacteria
D. The patient’s high fever inactivated the antibiotic,allowing the surviving bacteria to grown rapidly
Answer: B
Explanation: trust me