Answer:
chắc là câu B í
Explanation:
What is the valency of halogens?why
Answer:
-1
Explanation:
The volume of a 76.52 g sample of methane gas is 32.7 L at 26.9 °C and 4.45 atm. What will its volume be at 95.4 °C and 1.7 atm?
Answer:
The volume of a 76.52 g sample of methane gas is
32.7 L at 26.9 °C and 4.45 atm. What will its volume be at 95.4 °C and 1.7 atm?
hii pls help me to balance the equation and state the symbols thankss
Answer:
H2 + CuO======Cu + H2O
Explanation:
Cu is copper
H is hydrogen
H2O is water
O is oxygen
CuO is copper 11 oxide
Answer:
[tex]{ \bf{H _{2(g)} + CuO _{(s)} → Cu _{(s)} + H _{2} O _{(g)} }}[/tex]
It's balancing, hope it helps
PLZ HELP ME WITH MY WORK
Answer:
Explanation:
pretty sure its mixure.
El hipoclorito de sodio (NaClO), es vendido en una solución clara de ligero color verde-amarillento y un olor característico que se conoce con el nombre genérico Límpido, con una concentración del 6%. Pero para la desinfección de superficies el Límpido, debe ser diluido al 0,5%. Cuánto Límpido debemos sacar del recipiente para obtener 200 ml de una solución al 0,5%.
Respuesta:
16,7 mL
Explicación:
Paso 1: Información provista
Concentración inicial (C₁): 6%Volumen inicial (V₁): ?Concentración final (C₂): 0,5%Volumen final (V₂): 200 mLPaso 2: Calcular el volumen de la solución concentrada
Queremos preparar una solución diluida de hipoclorito de sodio a partir de una concentrada. Podemos calcular el volumen inicial que debemos tomar usando la regla de dilución.
C₁ × V₁ = C₂ × V₂
V₁ = C₂ × V₂ / C₁
V₁ = 0,5% × 200 mL / 6% = 16,7 mL
why do we shake syrup medicines before drinking
Answer:
The label may instruct you to shake a liquid medicine before using so that the active ingredients are evenly distributed throughout it.
Explanation:
Answer:
maybe because if somehow the liquids get separated then shaking them up would mix them back to how they are suppose to be originally.
Explanation:
help me pls! plsssss
Answer:
Neutron, neutral subatomic particle that is a constituent of every atomic nucleus except ordinary hydrogen. It has no electric charge and a rest mass equal to 1.67493 × 10−27 kg—marginally greater than that of the proton but nearly 1,839 times greater than that of the electron.
Explain how the existence of ions relates to the number of electrons present in atoms of an element? (A.P.E.X)
Answer:
if you have options please include them, but I'll give you an idea.
Explanation:
The existence of ions happens when atoms lose or gain electrons.
if an atom gains an electron it will become a negative ion (because electrons are negative, and you gained more negativity.)
if an atom loses an electron it will become a positive ion (because it has lost negativity, which is the electron that we've lost).
I hope it helps, if it does please mark me brainliest!
The seeds of a dandelion are wispy and very light. A single dandelion produces many seeds. How does the structure of the seeds relate to the dandelion's method of spreading seeds?
A Dandelion seeds are spread mainly by the wind. Because they are light, the wind can carry them. The dandelion produces many seeds because not all seeds will land in a good location to sprout.
B. Dandelion seeds are spread primarily by becoming attached to animals' fur. Because they are light, the animals can cany many without noticing. The dandelion produces many seeds because not all seeds will land in a good location to sprout
C. Dandelion seeds are spread mainly by animals that eat them Because they are light the animals will eat many seeds. The dandelion produces many seeds in order to outcompete other plants for resources
D. Dandelion seeds are spread primarily by moving water. Because they are light, they will float on the water. The dandelion produces many seeds in order to outcompete other plants for resources. SIMIT
Answer:
the answer will be number...D
Answer:
The answer is A
Explanation:
Because dandelions are wispy and very light, the slightest gasp of wind helps carry the dandelions to new locations and help reproduce the seed into a new dandelion.
Bài 19 với ạ, ai giúp em với ❤️❤️❤️❤️❤️
Answer:
we're are u from
Explanation:
also the writing from that paper look really cool
The first atmosphere a. consisted mainly of water, carbon dioxide, carbon monoxide, and methane. b. was replaced by a secondary atmosphere that, arguably, consisted partially of gases brought to the Earth by comets. c. was replaced by a secondary atmosphere only after the Earth developed gravity, which helped deflect the solar wind. d. dissolved into the Earth's oceans before it was replaced by a second atmosphere.
Answer:
Hence the correct option is option b - was replaced by a secondary atmosphere that, arguably, consisted partially of gases brought to the Earth by comets.
Explanation:
The first atmosphere was formed during the formation of the world.
But the secondary atmosphere formed mainly 2. billion years ago by earth's internal volcanic activity, or by the buildup of fabric from comet impacts.
Nal+ pb(SO4) 2 Pbl4 + Na2SO4 explain how to balance the chemical equation and classify its reaction type
Explanation:
because there are 4 Iodines on the left, we'll put. 4 in front of NaI to balance it. This would result in 4 Na on the left, so we'll put a 2 in front of Sodium Sulfate to balance the right side. Now we have 4 Na and I on both side, as well as 2 Sulfate on both sides. Pb is already balanced. The equation is now complete.
Which equation describes a physical change? i. H2O(s) ⟶ H2O(l) ii. Na+(aq)+Cl−(aq) +Ag+(aq)+NO3−(aq) ⟶ AgCl(s)+Na+(aq)+NO3−(aq) iii. CH3OH(g)+O2(g) ⟶ CO2(g)+H2O(g) iv. 2H2O(l) ⟶ 2H2(g)+O2(g) v. H+(aq)+OH−(aq)⟶ H2O(l)
Answer:
The answer is "Option i"
Explanation:
In this question, only option (i) is correct, and others were wrong which can be defined as follows:
In option (ii):
[tex]Na^+\ (aq)+Cl^- \ (aq) +Ag^+ \ (aq)+NO_3^- \ (aq) \to AgCl\ (s)+Na^+ \ (aq)+NO_3^-\ (aq) \\\\[/tex]
It is the complete ionic equation.
In option (iii):
[tex]CH_3OH\ (g)+O_2\ (g) \to CO_2\ (g)+H_2O\ (g)[/tex]
It is the combustion reaction but a not balanced equation.
In option (iv):
[tex]2H_2O\ (l) \to 2H_2\ (g)+O_2\ (g)[/tex]
It is the decomposition equation.
In option (v):
[tex]H^+\ (aq) +OH^-\ (aq)\to H_2O\ (l)[/tex]
It is the complete ionic equation.
1. In regards to curly hair, which of the following statements
are TRUE? (select 2 answer choices).
A. Curly hair develops over time. It is not acquired at birth.
B. Curly hair can lead to harmful mutations in the body.
C. Curly hair results from a change in the gene that
codes for hair structure.
D. People with curly hair have different hair protein structures than people with
straight hair.
Answer here:
Answer:
A and D are the answers
Explanation:
the other two don't make sense
The statements C and D are correct, i.e., curly hair have different protein structure from straight hair and curly hair results from a change in the gene.
What is protein?Proteins are biomolecules made of amino acids. Proteins are very essential to all living things and contributes the body structure. Proteins are mainly up taken through diet and they are the main source of energy.
Hair is made of keratin protein. Keratin makes up our skin and nails too.Curly hair is originating by birth not developing over time. Curly hair is more likely to be occurring through inheritance.
The protein structure the hair follicle is some more bend for curly hair. Curly hair and straight hair originates from different gene traits. The gene type is inherited from the parents.
Hence, for people with curly hair have different protein structure and it result from a change in gene that code for hair structure. Thus options C and D are correct.
To learn more about proteins, refer the link below:
https://brainly.com/question/2193769
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What is the quantity of carbon-14 in a bone after 17,190 years if the initial mass of C-14 is 0.300 grams and the half-life is 5,730 years?
A.
0.038 g
B.
0.093 g
C.
0.281 g
D.
0.412 g
A. 0.038 g.
Explanation:
The decay of carbon-14 is a first order reaction.
The rate constant of the reaction (k) in a first order reaction = ln (2)/half-life = 0.693/(5730 year) = 1.21 x 10⁻⁴ year⁻¹.
The integration law of a first order reaction is:
kt = ln [Ao]/[A]
k is the rate constant = 1.21 x 10⁻⁴ year⁻¹.
t is the time = 17,190 years.
[Ao] is the initial concentration of carbon-14 = 0.300 g.
[A] is the remaining concentration of carbon-14 = ??? g.
∵ kt = ln [Ao]/[A]
∴ (1.21 x 10⁻⁴ year⁻¹)(17,190 years) = ln (0.300 g)/[A]
2.08 = ln (0.300 g)/[A]
Taking exponential for both sides:
8.0 = (0.300 g)/[A]
∴ [A] = 0.0375 g ≅ 0.038 g
balanced chemical equation:Copper( ii) oxide solid +dilute sulphuric acid
Answer:
CuO + H2SO4 = CuSO4 + H2O
Reaction type: double replacement
Which of the following describes scientists?
О
A. People with only one perspective
B. People with similar personalities
C. People from different backgrounds
D. People with perfect understanding of science
57:17
A ball that has a mechanical energy of 65 J has 12 J of kinetic energy. The ball has blank
energy.
J of potential energy
Answer:
53 Joules
Explanation:
Applying the law of conservation of mechanical energy.
Law of conservation of mechanical energy: States that energy although, energy can not be transformed from one form to another, the total energy of the system remain the same.
I.e,
Mechanical Energy = E.K+P.E..................... Equation 1
Where E.K = Kinetic energy, P.E = Potential energy.
From the question,
Given: Mechanical energy = 65 Joules, K.E = 12 J
Substitute these values into equation 1 and solve for P.E
65 = 12+P.E
P.E = 65-12
P.E = 53 Joules
When under a pressure of 9.5 atm, a piston has a volume of 1.7 liters. It the piston is compressed to a
volume of 1.1 liters, what will the new pressure be?
c. 8.90 atm
a. 5.08 atm
b. 6.15 atm
d. 14.7 atm
Answer:
D
Explanation:
according to boyle's law the temperature and pressure of a gas are inversely proportional given by the equation
p1v1=p2v2
In this case p1 is 9.5,v1 is 1.7,v2 is 1.1 and we have to find p2
9.5×1.7=p2×1.1
16.15/11=1.1p2/1.2
p2=14.7
I hope this helps
Answer:
[tex]\boxed {\boxed {\sf D.\ 14.7 \ atm}}[/tex]
Explanation:
We are asked to find the pressure on a gas given a change in volume. We will use Boyle's Law which states the volume of a gas is inversely proportional to the pressure. The formula for this law is:
[tex]P_1V_1=P_2V_2[/tex]
The gas originally has a pressure of 9.5 atmospheres and a volume of 1.7 liters.
[tex]9.5 \ atm * 1.7 \ L = P_2V_2[/tex]
The gas is compressed to a volume of 1.1 liters, but the pressure is unknown.
[tex]9.5 \ atm * 1.7 \ L = P_2* 1.1 \ L[/tex]
We want to find the new pressure, so we must isolate the variable P₂. It is being multiplied by 1.1 liters. The inverse operation of multiplication is division. Divide both sides of the equation by 1.1 L.
[tex]\frac {9.5 \ atm * 1.7 \ L}{1.1 \ L} =\frac{ P_2* 1.1 \ L}{1.1 \ L}[/tex]
[tex]\frac {9.5 \ atm * 1.7 \ L}{1.1 \ L} =P_2[/tex]
The units of liters cancel.
[tex]\frac {9.5 \ atm * 1.7 }{1.1 } =P_2[/tex]
[tex]\frac {16.15}{1.1} \ atm =P_2[/tex]
[tex]14.6818181818 \ atm= P_2[/tex]
Round to the tenths place. The 8 in the hundredth place tells us to round the 6 up to a 7.
[tex]14.7 \ atm \approx P_2[/tex]
The new pressure at a volume of 1.1 liters is approximately 14.7 atmospheres.
Which factors ALL increase reaction rate?
decrease temperature, stir, increase surface area, remove catalyst
none of these
increase temperature, increase surface area, add catalyst, stir
increase temperature, stir, decrease surface area, add catalyst
Answer:
increase temperature, increase surface areas, add catalyst, stir
The rate of reaction can be increased with the increase in temperature, surface area, adding catalyst and allowing stirring. Thus, option C is correct.
What is rate of reaction?The rate of reaction is given as the rate of formation of product or the rate of disappearance of reactant in unit time.
The rate of reaction can be affected with:
Increase in temperature - It will increase the collisions between the reactants, and thereby the rate.Increase in surface area - It results in increased interaction of the reactant molecules for the formation of product.Catalyst - It lowers the activation energy of the reactant, and thereby increases the rate of reaction.Stirring - It mediates the increase in the collisions and the surface area, and resulting in increased rate of reaction.Thus, the rate of reaction can be increased with the increase in temperature, surface area, adding catalyst and allowing stirring. Thus, option C is correct.
Learn more about rate of reaction, here:
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hii pls help me to balance the equation and state the symbols thanksss
Answer:
I DID HOW I KNOW . I HOPE IT WILL HELP YOU :D
Write the expected ground electronic configuratio for the noble gas with electron occupying 4f orbitals?
Answer:
There are main six noble gases in the periodic table. The filling of 4f-orbitals occurs after 6s orbitals. The noble gas that belongs to the sixth period is Radon. Its electronic configuration is [ X e ] 6 s 2 4 f 14 5 d 10 6 p 6 .
Therefore, the name of noble gas is Radon.
PLZ HELP ME WITH MY WORK
How many different elements are there in the molecule C8H11NO2,?
A. 21
B. 2
c. 11
D. 4
Answer:
option C 11
is the correct answer
What are 5 uses of nitrogen?
Answer:
nitrogen is used in the production of 1) fertilisers 2) nitric acid 3) nylon 4) dyes and 5) explosives
please give me brainliest if you can :))
A piece of unknown metal with mass 68.6 g is heated to an initial temperature of 100 °C and dropped into 8.4 g of water (with an initial temperature of 20 °C) in a calorimeter. The final temperature of the system is 52.1°C. The specific heat of water is 4.184 J/g*⁰C. What is the specific heat of the metal?
0.171
0.343
1.717
3.433
Answer:
1.717
Explanation:
PLEASE URGENT HELP!! 30 POINTS!!!!!!
Answer:
CH³–C=CH——CH³–CH=CH²
Explanation:
THIS IS PROPYNE TO PROPENE
if 1.35 g of aluminum occupies 0.500 cm^3. what is the density of aluminum
Answer:
2.7
Explanation:
Density= mass/volume
= 1.35/0.500
= 2.7
What is the standard reduction potential, E, for the half-reaction Al3+ (aq)
3e- -> Al(s)?
Answer:
E° = -1.66 V
Explanation:
The standard reduction potential is also known as the standard electrode potentials and it tries to find the probability that an element will be reduced or undergo reduction.
From activation series online showing the standard reduction potentials for half cells, the standard reduction potential of Al3+ (aq) + 3e- -> Al(s) is;
E° = -1.66 V
PLZ HELP Question 14 of 25 What is the name for a representation of the physical world?
A. Model
B. Compound
C. Atom
D. Alloy SUBMIN
Answer:
Model
Explanation:
A model of anything is something you make to represent it in it's physical world form
HF or HCl which can form the hydrogen bond? Explain your answer.
Answer:
can only form one hydrogen bond each
Explanation:
can only form one hydrogen bond each
