Answer:
Explanation:
water
H. 2. O is the chemical formula for water, meaning that each of its molecules contains one oxygen and two hydrogen atoms
Can someone please help me
Answer:
white
Explanation:
Which is larger?
1). 1 liter or 1500 milliliters
2) 12 cm or 12 milliliters
Answer:
1). 1 litre
2).12 cm
Explanation:
In 1 litre = 1000 ml whereas 1500 milliliters equals 0.15 litres and it is same for 12 cm and 12 milliliters
What was alchemy?
A. A part of chemistry that experimented only with metals
B. An area of research that investigated all areas of science using
chemistry
C. An early form of chemistry based on experiments and evidence to
test ideas
D. An attempt to turn cheap metals into gold and develop potions using superstitious practices
Answer:
D
Explanation:
its a very old study and philosophy of how to change basic substances such as metals into other substances
GABReva 2. Explain the usefulness of friction
Answer:
Friction always slows a moving object down. ... Friction can be a useful force because it prevents our shoes slipping on the pavement when we walk and stops car tyres skidding on the road. When you walk, friction is caused between the tread on shoes and the ground. This friction acts to grip the ground and prevent sliding.
Which TWO properties of water make it
essential for supporting the
development of life? (Again, there
are TWO answers here, be sure to check
both of them!
Water has all the ingredients needed to
create lite.
Water allows biomolecules (like proteins) to
move around and react with one another.
Life gets thirsty and needs to stay
hydrated.
EN
INTL
WS
Water helps regulate temperature so it
doesn't get too hot or too cold.
8
53
Answer:
oooooooooougifufofhhdykddykyd
Give reasons. 1. There is interrelation between wildlife and vegetation 2. Various activities of the man have helped for the survival of the wildlife. 3. Establishment of national parks and wildlife conservation area help for the protection of wildlife. 4. Different animals are put under Red List. 5. Giant hornbill is critically endangered species in Nepal. Answer the following questions.
Answer:
Yes
Explanation:
Identify the products represented by letters A-F to complete each chemical equation, then write the net ionic equations for the reactions including the physical states of reactants and products. Use the standard enthalpies of formation to calculate the changes in the standard enthalpies of reaction.
a) NaOH(aq)+HCl(aq)⟶A(aq)+B(l)
A=
B=
Balanced net ionic equation:
Δ0rxn=
b) NaOH(aq)+NH4Cl(aq)⟶C(aq)+D(aq)+E(l)
C=
D=
E=
Balanced net ionic equation:
Δ0rxn=
c) HCl(aq)+NH3(aq)⟶F(l)
F=
Balanced net ionic equation:
Δ0rxn=
The product of a chemical reaction is what is remaining at the end of the reaction. The combination between reactant to form products can happen in a variety of ways including combination of ions in a solution to form new compounds
The correct compounds representing the variables and the net ionic equations are as follows:
a) A = NaCl
B = H₂O
Balanced net ionic equation: OH⁻(aq) + H⁺(aq) → H₂O (l)
ΔHrxn = Negative
b) C = NH₃
D = NaCl(aq)
E = H₂O(l)
Balanced net ionic equation: OH⁻(aq) + NH₄⁺(aq) → NH₃(aq) + H₂O(l)
ΔHrxn = Negative
c) F = NH₄Cl(aq)
Balanced net ionic equation: H⁺(aq) + NH₃(aq) → NH₄⁺(aq)
ΔHrxn = Negative
The reason the above values are correct are as follows:
a) Part (i)
The given chemical equation is
NaOH(aq) + HCl(aq) → A(aq) + B(l)
The chemical equation is the reaction between sodium hydroxide NaOH (aq) and hydrochloric acid HCl (aq), the product of the reaction is sodium chloride and water as follows;
NaOH(aq) + HCl(aq) → NaCl(aq) + H₂O(l) + Heat
Therefore, we have;
A = NaCl, and B = H₂O
Part (ii)
The ionic equation is given as follows;
Na⁺(aq) + OH⁻(aq) + H⁺(aq) + Cl⁻(aq) → Na⁺(aq) + Cl⁻(aq) + H₂O (l)
Given that Na⁺(aq) and Cl⁻(aq) are spectator ions in the reaction, we have the balanced net ionic equation given as follows;
Balanced net ionic equation: OH⁻(aq) + H⁺(aq) → H₂O (l)
Part (iii)
ΔHrxn = Negative
b) Part (i)
The given chemical equation is NaOH(aq) + NH₄Cl(aq) → C(aq) + D(aq) + E(l)
The given reaction is between sodium hydroxide, NaOH(aq) and ammonium chloride, NH₄Cl(aq) and the products of the reaction are dissolved ammonia NH₃(aq), sodium chloride NaCl(aq), and water H₂O(l)
Therefore, we have;
NaOH(aq) + NH₄Cl(aq) → NH₃(aq) + NaCl (aq) + H₂O(l) + Heat
Therefore;
C = NH₃, D = NaCl(aq), E = H₂O(l)
Part (ii)
The ionic equation for the reaction is given as follows;
Na⁺(aq) + OH⁻(aq) + NH₄⁺(aq) + Cl⁻(aq) → NH₃(aq) + Na⁺(aq) + Cl⁻(aq) + H₂O(l)
The Na⁺(aq) and Cl⁻(aq) occur in both the reactants and products, therefore, they cancel out as spectator ions and we have;
Balanced net ionic equation: OH⁻(aq) + NH₄⁺(aq) → NH₃(aq) + H₂O(l)
Part (iii)
ΔHrxn = Negative
c) Part (i)
HCl(aq) + NH₃(aq) → F(l)
The given reaction is between hydrochloric acid and aqueous ammonia which has the product as ammonium chloride, NH₄Cl
Therefore, the reaction is given as follows;
HCl(aq) + NH₃(aq) → NH₄Cl(aq) + Heat
∴ F = NH₄Cl(aq)
Part (ii)
The ionic equation is given as follows;
H⁺(aq) + Cl⁻(aq) + NH₃(aq) → NH₄⁺(aq) + Cl⁻(aq)
Therefore, the chlorine ion Cl⁻(aq) occurs in both the reactant and product and can therefore, can be canceled out, and we have;
Balanced net ionic equation: H⁺(aq) + NH₃(aq) → NH₄⁺(aq)
Part (iii)
ΔHrxn = Negative
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any integrated chem buffs out there?
The field of study that Christian Doppler's work influenced the most was about light waves.
Hope it helps you.
will mark brainliest if correct
Answer:
that would be B
Explanation:
In the reaction 2H2 + O2 + H20, what coefficient should be placed in front of H2O to balance the reaction? 0 2 03 O 4
Answer:
2
Explanation:
2×2
2O
soooo
2H2O means 4H2O
This is a model of a water molecule which has two hydrogen atoms and one oxygen atom. Why ISN'T water considered to be a MIXTURE?
A.
Because the Hydrogen & Oxygen (or O & H) atoms bonded chemically
B.
Because the Hydrogen & Oxygen atoms are easily separated
Facts, figures, and other evidence learned through observation are call
Answer:
DataExplanation:
Data are the facts, figures, and other evidence gathered through observations.
What is 3780 cal to kJ
Answer:
15815.52 kJ
Explanation:
What is the triangle law of vector quantity
Answer:
A law which states that if a body is acted upon by two vectors represented by two sides of a triangle taken in order, the resultant vector is represented by the third side of the triangle.
Explanation:
How should you add metal to the graduated cylinder so that it will not crack the glass at the bottom?
Get the metal as close to thn
Answer:
you tilt the cylinder at a slight angle so that the metal slides down the sides, rather than drops all it`s weight to the bottom
does the law of conservation apply to burning fossil fuels
Answer: yes
Explanation:
While burning fossil fuels energy is under going a chemical reaction but the matter/energy itself is not being destroyed or created
Answer:
The law of conservation applies to the burning fossil fuels
Explanation:
When you burn fossil fuels, some of the energy is transformed into other types of energy, and some of it is transferred to other objects, yet the energy is neither destroyed or created, so it applies to the law of conservation.
Round each number to four significant figures
a. 84,791
b. 256.75
C. 431,801
d. 0.00078100
Answer:
a.
84,791 » 8479
b.
256.75 » 256.8
c.
431,801 » 4318
d.
0.00078100 » 0.0007810
Explanation:
[tex].[/tex]
What do we call planets that are not in our solar system
Answer in word.
1)What is the principal of chromatography?
Answer:
chromatography is based on the principle where molecules in mixture applied onto the surface or into the solid, and fluid stationary phase is separation from each other while moving with the aid of a mobile phase.
Can you join please.
It's urgent for help.
which equation is used to calculate the free energy change of a reaction
Answer:
B bcx is a way of separating different crystals from each other and the other is a way of separating different crystals from each other and the other
Calculate the empirical formula of a compound that has a composition of 5.9% (by mass) hydrogen and 94.1% (by mass) oxygen.
Answer:
The empirical formula is the simplest form;
Given:
Oxygen O at 94.1% and
H at 5.9%
Assume 100grams.
94% = 0.941 x 100gm. = 94.1 gm x 1mole/16gm. = 5.88 moles of O
5.9% = 0.059 x 100gm. = 5.9gm. X 1moleH/1.002gm. = 5.88 moles of H
There is one mole of O for each mole of H so the empirical formula is [tex]O_1H_1[/tex]
and written as OH.
Explanation:
[tex]given \: that \: oxygen \: by \: 94.1\% (.941)\\ hydrogen \: by5.9\%(.059) \\ in \: 100gram \: \\ oxygen = 100 g\times .941 = 94.1 \times \frac{1(mol)}{16g} \\ = 5.88moles \: of \: oxygen \\ in \: hydrogen \: = .059\times 100 = 5.9 \times \frac{1mol}{1.002gram} \\ = 5.88mole \: of \: hydrogen \\ \: so \: here \: \: both \: oxygen \: andhydrogen = 5.88 \\their \: ratio = 1 \: 1 \\ so \: emparical \: formula = oh \\ thank \: you[/tex]
The table shows the charge on three unknown subatomic particles,
Charged Particles
Particle Charge on Particle
A
Positive
B
B
No charge
С
Negative
Which particle is most likely present in the nucleus of the atom?
O Only particle A
O Only particle C
O Both particles A and B
Both particles B and C
Answer:
Both particles A and B
Explanation:
A nucleus contains both protons and neutrons .
But protons are positively charged whereas neutrons have no charge.
[tex].[/tex]
Both particles A and B are most likely present inside the nucleus of the atom. Therefore, option (c) is correct.
What is the nucleus of an atom?The nucleus of an atom contains the particles protons and neutrons. Both the solid particles in an atom are responsible for 99.9% of the mass in the nucleus.
The protons are the positively charged particles that lie inside the nucleus. Therefore, the nucleus of an atom has a positive charge on it while the negatively charged electrons rotate around the nucleus.
The neutrons do not carry any charge. So we can say that the neutrons are neutral. Therefore, the charge on the nucleus is only due to protons.
The atomic powers which are holding the protons and the neutrons inside the nucleus are also vast. The protons are prsent very close to each other inside the tiny nucleus, so the electrostatic forces of repulsion act in the nucleus.
Therefore, particles with no charge and positive charge are most present in the nucleus of the atom.
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A sample of brass weighing 1.203g was analyzed. The zinc in the alloy was reacted with 35.123g of HCl in excess, according to the balanced equation:
Zn (s) + 2HCl(aq) - > H2(g) + ZnCl2 (aq)
After all the zinc reacted, the mass of the remaining solution weighed 36.309g
What was the mass of H2 produced?
What mass of Zn reacted?
What was the percentage of Zn (by mass) in the alloy?
The number of moles of reactants and products can be used to obtain the mass of products formed. The results obtained are as follows;
The mass of hydrogen produced is 0.0174 gramsThe mass of zinc produced is 0.5688 gramsThe percentage by mass of zinc in the brass alloy is 47.3 %The question says that HCl was in excess. It means that after the reaction, we will have unreacted HCl(aq) and ZnCl2(aq) in the remaining solution.
Hence;
Mass of ZnCl2(aq) formed = 36.309g - 35.123g = 1.186g
Number of moles ZnCl2(aq) formed = [tex]\frac{mass of ZnCl2(aq) formed}{molar mass of ZnCl2}[/tex]
[tex]\frac{1.186g}{136.286 g/mol}[/tex] = 0.0087 moles
From the reaction equation;
[tex]Zn (s) + 2HCl(aq) - > H2(g) + ZnCl2 (aq)[/tex]
To obtain the amount of Zn reacted
1 mole of Zn yields 1 mole of ZnCl2
x moles of Zn yields 0.0087 moles of ZnCl2
x = 0.0087 moles of Zn
a) 1 mole of Zn yields 1 mole of H2
0.0087 moles of Zn yields 0.0087 moles of H2
Mass of H2 = 0.0087 moles of H2 * 2 g/mol = 0.0174 grams
b)
Mass of Zn reacted = 0.0087 moles of Zn * 65.38 grams/mole = 0.5688 grams
c)
Percentage of Zn in the alloy = 0.5688 grams/1.203g * 100 = 47.3 %
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plss help me :((
The beaker above will measure up to [ ] mL.
What number would be printed on this beaker between 100 and 150? [ ]
What number would be printed on this beaker between 150 and 200? [ ]
Answer:
250mL, 125mL, 175mL
Explanation:
The beaker has graduated marks every 25mL after the 50mL mark.
Answer:
250ml 125ml 175ml and also do you attend GOC ?
cause same lol
Explanation:
What volume of HCl must be used to prepare 350mL of 2.0M HCl solution using a stock solution containing 5L of 12.0M HCl?
Answer:
~58.3 mL
Explanation:
m1*v1=m2*v2 --> (12.0 M HCL) * v1 = 350mL * 2.0M HCL
--> 350*2.0 = 700
--> 700/12.0 M HCL = 58.3 mL repeating
The gas in an aerosol can is at a pressure of 3.10 atm at 25 degrees Celsius. Directions on the can warn the user not to keep the can in a place above 52 degrees Celsius. What would the gas pressure in the can be at 52 degrees Celsius
Answer:
[tex]\boxed {\boxed {\sf 6.4 \ atm}}[/tex]
Explanation:
We are asked to find the pressure of a gas in a can given a change in temperature. We will use Gay-Lussac's Law, which states the pressure of a gas is directly proportional to the temperature. The formula for this law is:
[tex]\frac {P_1}{T_1}= \frac {P_2}{T_2}[/tex]
Initially, the gas in the aerosol can has a pressure of 3.10 atmospheres at a temperature of 25 degrees Celsius.
[tex]\frac { 3.10 \ atm}{25 \textdegree C}=\frac{P_2}{T_2}[/tex]
The temperature is increased to 52 degrees Celsius, but the pressure is unknown.
[tex]\frac { 3.10 \ atm}{25 \textdegree C}=\frac{P_2}{52 \textdegree C}[/tex]
We are solving for the new pressure, so we must isolate the variable [tex]P_2[/tex]. It is being divided by 52 degrees Celsius. The inverse operation of division is multiplication, so we multiply both sides of the equation by 52 °C.
[tex]52 \textdegree C *\frac { 3.10 \ atm}{25 \textdegree C}=\frac{P_2}{52 \textdegree C} * 52 \textdegree C[/tex]
[tex]52 \textdegree C *\frac { 3.10 \ atm}{25 \textdegree C}=P_2[/tex]
The units of degrees Celsius cancel.
[tex]52 *\frac { 3.10 \ atm}{25}=P_2[/tex]
[tex]52 *0.124 \ atm = P_2[/tex]
[tex]6.448 \ atm = P_2[/tex]
The original values of pressure and temperature have 2 and 3 significant figures. Our answer must be rounded to the least number of sig figs, which is 2. For the number we calculated, that is the tenths place. The 4 in the hundredth place tells us to leave the 4 in the tenths place.
[tex]6.4 \ atm \approx P_2[/tex]
The gas pressure in the can at 52 degrees Celsius is approximately 6.4 atmospheres.
how did they start water conservation in tamil nadu . short answer
Answer:
Historically,Tamil Nadu is known for its temple tanks and community tanks that not only save water for summer but also act as artifical ground water recharge structures. It also set an example by making rain water harvesting mandatory in all building. But now water crisis associated with monsoon failure for consecutive years had lead it to a desperate situation.
Which statements describe density? Check all that apply.
Density is a chemical property of an object.
The density of an object is constant.
Density is a derived unit of measure.
Density is the sum of the mass and volume of an object.
The density of an object determines whether it will sink or float.
( pick multiple)
Answer:
density is the sum of the mass and volume of an object
Calculate the mass of a liquid with a density of 0.92g/ml and a volume of 15 ml
Answer:
13.8g
Explanation:
Remember that density is equal to mass over volume
d=m/v
rearrange the problem and you get dv=m
(0.92g/mL)(15mL)=13.8g
Los elementos que forman aniones con carga -1 y una capa externa estable de ocho electrones pertenecen al grupo de los:
Los elementos que forman aniones con carga -1 y una capa externa estable de ocho electrones pertenecen al grupo de los: halógenos.
Para alcanzar la estabilidad, los átomos siguen la regla del octeto: ganan, pierden o comparten electrones para tener 8 electrones en su capa externa (capa de valencia).
Los elementos del Grupo 17 de la Tabla Periódica, conocidos como halógenos, tienen 7 electrones en su capa de valencia. Así, tienden a ganar 1 electrón para completar su octeto. Como los electrones tienen carga negativa, al ganar 1 electrón los aniones quedan con una carga de -1.
Puedes aprender mas sobre la regla del octeto aquí: https://brainly.com/question/18892451