Which represents the smallest percentage of earths water a.frozen water b. Ground water c. Salt water d.surface fresh water
ANSWER: Surface Fresh Water
Humans only use 0.3% of the water on earth. The other 99.7 percent is in the oceans, soils, icecaps, and floating in the atmosphere.
What is the number of moles in 0.025g (NH4)2Cr2O7
Answer:
9.91 X 10^-5 or 0.000099 mol
Explanation:
The molecules that make up soap have a region that contains polar covalent bonds and a region that contains nonpolar covalent bonds. How does this property explain the ability of soap molecules to help remove oils from your skin when you wash?
Explanation:
The cleansing action of soaps is predicated on the nature of soaps as we have it.
A soap has the ability to remove dirt from materials. The cleansing action of a soap is related to the structure of its molecule. A molecule of soap has dual structure with polar head that is water loving and a long hydrocarbon tail which is hydrophobic. The structure enables soap molecules to emulsify an organic dirt present on a fabric in water. The soap causes the suspension of tiny oil droplets in the aqueous medium.Determine the formula for rhodium (II) nitrate.
Answer:
Yup this is right. I checked! Rhodium(II) nitrate | H2N2O6Rh+2 - PubChem.
Explanation:
Monique hears on the weather report that cold, dry air from Canada is going to hit warm, moist air from the Gulf of Mexico. She should expect a:
Answer:
She should suspect a Tornado.
Explanation:
Tornadoes form when warm humid air collides with cold dry air. The denser the cold air is pushed over warm air, causing an updraft. As soon as it reaches the ground a tornado is formed.
how many grams of magnesium oxide are formed if 20.9 grams of Mg and 15.2 g of O2 react.
Answer:
Mass of magnesium oxide formed = 35.1 g
Explanation:
Given data:
Mass of Mg = 20.9 g
Mass of O₂ = 15.2 g
Mass of magnesium oxide formed = ?
Solution:
Chemical equation:
2Mg + O₂ → 2MgO
Number of moles of Mg:
Number of moles = mass/molar mass
Number of moles = 20.9 g/ 24 g/mol
Number of moles = 0.87 mol
Number of moles of O₂:
Number of moles = mass/molar mass
Number of moles = 15.2 g/ 32 g/mol
Number of moles = 0.475 mol
Now we will compare the moles of MgO with magnesium and oxygen.
Mg : MgO
2 : 2
0.87 : 0.87
O₂ : MgO
1 : 2
0.475 : 2/1×0.475 = 0.95
Number of moles of MgO formed by Mg are less thus Mg will limiting reactant.
Mass of MgO:
Mass = number of moles × molar mass
Mass = 0.87 mol × 40.3 g/mol
Mass = 35.1 g
Which equation has both a liquid and a gas as products?
A) 2 upper Hg upper O (s) right arrow 2 upper H g (l) plus upper O subscript 2 (g).
B) 2 upper M g (s) plus upper O subscript 2 (g) right arrow 2 upper M g upper O (s).
C) 1 UJpper K upper C l upper O subscript 3 (s) right arrow 2 upper K upper C l (s) plus 3 upper O subscript 2 (g).
D)
Upper M g (s) plus 2 upper H upper C l (a q) right arrow upper H subscript 2 (g) plus upper M g upper C l subscript 2 (a q).
Answer:
A) 2 upper Hg upper O (s) right arrow 2 upper H g (l) plus upper O subscript 2 (g).
Explanation:
Elements or compounds can be combined or degraded to form new substances called PRODUCTS. In chemistry, the state in which the substances reacting or being formed are is represented using signs in brackets.
(s) means solid state
(aq) means aqueous state
(l) means liquid state
According to this question, in the reaction between: 2 upper Hg upper O (s) right arrow 2 upper H g (l) plus upper O subscript 2 (g). This can be chemically written as:
2HgO (s) → 2Hg (l) + O2 (g)
From this equation, it can be observed that Mercury (Hg) and oxygen (02), which are the products are in a liquid and gaseous state respectively as shown by the sign.
Answer:
Other person is correct it is A.
Explanation:
If a 3.0 M solution of glucose (C6H12O6), a 2.0 M solution of Na2SO4 and a 1.0 M solution of (NH4)3PO4, is made, which solution will have the lowest vapor pressure, highest boiling point, and lowest freezing point?
Answer:
[tex]Na_{2}SO_{4}[/tex]
Explanation:
In the case when there are more ions present in the solution so that solution contains less vapour pressure, high boiling point and less freezing point
Given that
[tex]Na_{2}SO_{4} \rightarrow 2Na+ + SO_{4}^{-2}[/tex]
Now the ions present would be
= 2.0 × 3
= 6 ions
These ions represent the greater among all the solutions available
Therefore the [tex]Na_{2}SO_{4}[/tex] is the right answer
The same is to be considered
Answer: Na2SO4
Explanation:
Explain how mixture melting points can be helpful in distinguishing between two compounds that have essentially the same melting point.
PLEASE HELPPPPPPPPPPPP
Answer:
lol good luck
Explanation:
Answer:
375.15
Explanation:
i used a calculator. hope it helped 8)
Most of the elements to the left of the stair-step line in the periodic table exist as _________ in the periodic table.
A. Gases.
B Liquids.
C. Plasmas.
D. Solids.
Most of the elements to the left of the stair-step line in the periodic table exist as liquids in the periodic table and the correct option is option B.
What is periodic table?
The periodic table is a tabular arrangement of the chemical elements by increasing atomic number which displays the elements so that one may see trends in their properties.
Elements are arranged from left to right and top to bottom in the order of their increasing atomic numbers. Thus,
Elements in the same group will have the same valence electron configuration and hence, similar chemical properties.Whereas, elements in the same period will have an increasing order of valence electrons. Therefore, as the energy level of the atom increases, the number of energy sub-levels per energy level increases.Therefore, Most of the elements to the left of the stair-step line in the periodic table exist as liquids in the periodic table and the correct option is option B.
Learn more about Periodic Table, here:
https://brainly.com/question/11155928
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What volume of silver will weigh exactly 2500 g. The density of silver is 10 g/cm3.
Answer:
250 cm³Explanation:
The volume of a substance when given the density and mass can be found by using the formula
[tex]volume = \frac{mass}{density} \\[/tex]
From the question we have
[tex]volume = \frac{2500}{10} \\ [/tex]
Wr have the final answer as
250 cm³Hope this helps you
A basketball with a mass of 0.60 kg is accelerated with a force of 10.8 N. If resisting forces
are ignored, what is the acceleration of the basketball to the nearest m/s 2
Answer:
18 m/s²Explanation:
The acceleration of an object given it's mass and the force acting on it can be found by using the formula
[tex]a = \frac{f}{m} \\ [/tex]
f is the force
m is the mass
From the question we have
[tex]a = \frac{10.8}{0.6} \\ [/tex]
We have the final answer as
18 m/s²Hope this helps you
A total of 6.28 x 10^5 J is taken from a heat source at 150.0 degrees Celsius and rejected to a heat sink at 50.0 degrees Celsius. Find (a) the change of entropy of in the heat source and heat sink separately and (b) the entropy change in the total system.
Answer:
Explanation:
a)
change in entropy of source = heat taken / temperature of source
= 6.28 x 10⁵ / (273 + 150)
= 628000 / 423
= 1484.63 JK⁻¹ ( decrease in entropy )
heat rejected in sink = 628000 x (273 + 50) / 423
= 628000 x 323 / 423
= 479536.64 J
change in entropy of sink = heat rejected / temperature of sink
= 479536.64 / (273 + 50)
=479536.64 / 323
= 1484.63 JK⁻¹ ( increase in entropy )
b )
net entropy change in the system
= +1484.63 - 1484.63
= zero.
How could you draw a model of the element copper to show that it is different from the element gold?
Answer:
You could color it different. Explain in a picture the difference. There are so many different variety's.
Explanation:
Name two (2) reasons and describe why it is important for you fo find a job that matches your skills, interests and abilities when searching for a career.
Answer:
It is important for you find a job that matches your skills, interests and abilities when searching for a career because then you will be satisfied with what you do and your career because since it fits your wants, skills, interests and abilities you will do a great job while working and completing tasks. Overall you'll be happy because that's the perfect job for you.
Explanation:
A CaCl2 solution is given to increase blood levels of calcium. If a patient receives 6.1 mL of a 12 % (m/v) CaCl2 solution, how many grams of CaCl2 were given?
Mass of CaCl₂ = 0.732 g
Further explanationThe concentration of a substance can be expressed in several quantities such as moles, percent (%) weight / volume,), molarity, molality, parts per million (ppm) or mole fraction. The concentration shows the amount of solute in a unit of the amount of solvent.
[tex]\tt \%(m/v)\rightarrow 12\%=\dfrac{mass~CaCl_2}{volume~of~solution}\times 100\%\\\\mass~CaCl_2=12\%\times 6.1\div 100\%\\\\mass~CaCl_2=0.732~g[/tex]
During the production of yogurt, specific ___________ are used to ferment the milk. In turn, the same ___________ are beneficial to our digestive system when we eat the yogurt.
Question 10 options:
A)algae
B)bacteria
C)fungi
D)protozoan
I will give you brainlest
Write balanced net ionic equations and the corresponding equilibrium equations for the stepwise dissociation of the triprotic acid H3PO4.
Answer:
[tex]H_3PO_4(aq)+H_2O(l)\rightleftharpoons H_3O^+(aq)+H_2PO_4^{-}(aq); \ Ka_1[/tex]
[tex]H_2PO_4^{-}(aq)+H_2O(l)\rightleftharpoons H_3O^+(aq)+HPO_4^{-2}(aq); \ Ka_2[/tex]
[tex]HPO_4^{-2}(aq)+H_2O(l)\rightleftharpoons H_3O^+(aq)+PO_4^{-3}(aq); \ Ka_3[/tex]
Explanation:
Hello!
In this case, since the phosphoric acid is a triprotic acid, we infer it has three stepwise ionization reactions in which one hydrogen ion is released at each step, considering they are undergone due to the presence of water, thus, we proceed as follows:
[tex]H_3PO_4(aq)+H_2O(l)\rightleftharpoons H_3O^+(aq)+H_2PO_4^{-}(aq); \ Ka_1[/tex]
[tex]H_2PO_4^{-}(aq)+H_2O(l)\rightleftharpoons H_3O^+(aq)+HPO_4^{-2}(aq); \ Ka_2[/tex]
[tex]HPO_4^{-2}(aq)+H_2O(l)\rightleftharpoons H_3O^+(aq)+PO_4^{-3}(aq); \ Ka_3[/tex]
Moreover, notice each step has a different acid dissociation constant, which are quantified in the following order:
Ka1 > Ka2 > Ka3
Best regards!
who can help me on this one ?
Answer:
eight strong bonds to the atoms that it touches and six weaker bonds to the atoms it almost touches. This makes it easier to understand why a metal might prefer the body-centered cubic structure to the hexagonal or cubic closest-packed structure.
5. In order for a bowling ball to move down the lane and strike pins, what must be applied to the ball?
(ICP.1.2)
A. A force less than any other forces that might act on the ball such as gravity or friction.
B. A force equal to any other force that might act on the ball such as gravity or friction.
C. A force greater than any other forces that might act on the ball such as gravity or friction.
D. A force that creates engugh friction for the ball to move down the lanes and hit the pins.
Answer:
c i think
Explanation:
Please answer the following three questions as completely as possible. No one sentence answers will be graded. These should be more in-depth answers and require some thinking:
What are some of the relationships among thermal energy, kinetic energy, particle movement, and temperature?
please answer this its due in 30 minutes
Answer:
pwede po ba tagalog
Explanation:
question ko lang po
Answer:
particle movement = kinetic energy = thermal energy = temperature.
Explanation:
kinetic energy is the force that an object in motion possesses. the particles of every substance are in motion and so they all possess kinetic energy. so if a particle moves more vigorously, it has more kinetic energy.
temperature is how hot or cold a substance is. particles with more thermal energy have higher temperatures. thermal energy comes from the kinetic energy of a substance. so the more kinetic energy the object possess, the more thermal energy they will have.
when a particle moves faster, it gains kinetic energy. this means its thermal energy increases and therefore its temperature increases.
In a chemical formula, what is used to indicate the number of atoms of each element?
spent lead-acid batteries are exempt from hazardous waste regulations if they are: a. stacked recycled b. thrown away c. stored outside
Answer:
It’s A
Explanation: they stack the waste batteries and then recycle it
Identify each substance as an acid or a base and write a chemical equation showing how it is an acid or a base according to the Arrhenius definition.
(a) H2SO4(aq)
(b) Sr(OH)2(aq)
(c) HBr(aq)
(d) NaOH(aq)
Answer:
(a) Acid
(b) Base
(c) Acid
(d) Base
Explanation:
According to the Arrhenius acid-base theory:
An acid is a substance that releases H⁺ in aqueous solution.A base is a substance that releases OH⁻ in aqueous solution.(a) H₂SO₄ is an acid according to the following equation:
H₂SO₄(aq) ⇒ 2 H⁺(aq) + SO₄²⁻(aq)
(b) Sr(OH)₂ is a base according to the following equation:
Sr(OH)₂(aq) ⇄ Sr²⁺(aq) + 2 OH⁻(aq)
(c) HBr is an acid according to the following equation:
HBr(aq) ⇒ H⁺(aq) + Br⁻(aq)
(d) NaOH is a base according to the following equation:
NaOH(aq) ⇒ Na⁺(aq) + OH⁻(aq)
Which conjugate acid/base pair could be used to create a pH 3.20 buffer solution with the largest possible buffercapacity?
a. Sulfurous acid/sodium bisulfite pKa=1.92
b. Hydrofluoric acid/sodium fluoridepKa=3.14
c. Nitrous acid/sodium nitritepKa=3.34
d. Benzoic acid/sodium benzoate pKa=4.20
e. Acetic acid/sodium acetate pKa=4.74
Answer:
b. Hydrofluoric acid/sodium fluoride (pKa=3.14).
Explanation:
Hello!
In this case, since the buffer capacity is related to how good a buffer behaves under the addition of acidic or basic substances in the light of holding the pH as constant as possible, we need to keep in mind that the best buffer must have a pKa as close as possible to the desired pH, that is, if the desired pH here is 3.20, we must pick the acid/base pair which the pKa cosest to 3.20.
In such a way, since b. Hydrofluoric acid/sodium fluoride (pKa=3.14 ) and c. Nitrous acid/sodium nitrite (pKa=3.34) have a pKa close to 3.20, the closest one is b. Hydrofluoric acid/sodium fluoride pKa=3.14 which is 0.06 pH units away from the desired pH, therefore the answer is b. Hydrofluoric acid/sodium fluoride pKa=3.14.
Best regards!
What is the percent yield of titanium (IV) oxide, if 10.2 g are formed when 25.7
g of titanium (IV) chloride react?
TiCl4 (s) + O2 (g) - TiO2 (s) + 2 Cl2 (g)
Answer:
Percent yield = 91%
Explanation:
Given data:
Percent yield of TiO₂ = ?
Actual yield = 10.2 g
Mass of TiCl₄ react = 25.7 g
Solution:
Chemical equation:
TiCl₄ + O₂ → TiO₂ + 2Cl₂
Number of moles of TiCl₄:
Number of moles = mass/molar mass
Number of moles = 25.7 g/ 189.7 g/mol
Number of moles = 0.14 mol
Now we will compare the moles of TiCl₄ and TiO₂.
TiCl₄ : TiO₂
1 : 1
0.14 : 0.14
Theoretical yield:
Mass = number of moles ×molar mass
Mass = 0.14 mol × 79.86 g/mol
Mass = 11.2 g
Percent yield:
Percent yield = [actual yield / theoretical yield ] × 100
Percent yield = [10.2 g / 11.2 g ]× 100
Percent yield = 91%
Helium gas in a cylinder is under 1.12atm pressure at 25.0C. What will be the pressure if the temperature increases to 37.0C?
Answer:
[tex]p_2=1.17atm[/tex]
Explanation:
Hello!
In this case, considering that the Gay-Lussac's law allows us to relate the temperature-pressure problems as directly proportional relationships:
[tex]\frac{p_2}{T_2} =\frac{p_1}{T_1} \\\\[/tex]
Thus, for the initial pressure and temperature in kelvins the final temperature in kelvins, we compute the final pressure as:
[tex]p_2=\frac{p_1T_2}{T_1} \\\\p_2=\frac{1.12atm*310.15K}{298.15K}\\\\p_2=1.17atm[/tex]
Best regards!
Magnesium metal is added to excess acid to generate hydrogen gas, which is collected over water at 25.0°C (vapour pressure of water is 23.8 mm Hg). The volume of the mixture is 0.0251 m3, and its total pressure is 96.4 kPa. Determine the amount of magnesium used in the reaction. Mg + 2H+ --> H2 (g) + Mg2+
Answer:
Explanation:
PV / RT = n , n is number of moles
Total pressure = 96400 Pa
vapour pressure = 23.8 mm of Hg
= .0238 x 13.6 x 10³ x 10 Pa = 3236.8 Pa
Pressure of hydrogen gas P = 96400 - 3236.8
= 93163.2 Pa
n = 93163.2 x .0251 / 8.31 x 298
= .944 moles of hydrogen gas is produced
moles of magnesium reacted = .944
grams of magnesium reacted = .944 x 24 = 22.66 grams .
what is the ratio of atoms of potassium to atoms of oxygen