Answer:
Explanation:
When a flask is dipped in very hot water in a large beaker , the flask expands due to heat gain . As a result , level of water in tube fitted in flask goes down .
After some time , the water inside tube also become hot so it expands . coefficient of volume expansion of water is more than coefficient of volume expansion of glass . Hence greater expansion takes place in the volume of water . It is due to this fact that water level in tube starts rising after some time of fall .
Which of the following is a halogen?
O A. Neon (Ne)
B. Iodine (1)
O C. Oxygen (0)
O D. Potassium (K)
Answer:
[tex]\boxed{\mathrm{Iodine}}[/tex]
Explanation:
Halogens are elements in group 17 or 7 in the periodic table.
Iodine is a halogen.
Therefore, iodine, an Halogen
Learn more at: https://brainly.com/question/15852546?referrer=searchResults
hi :) , if the density of an object is the same as water , will the object float or sink?
Answer:
it will float if the object is 1g/cm^3(water 's density ) because it is less dense
pls help...
You are a forensic scientist working on a murder case. You have taken the blood sample from the crime scene and put it through Electrophoresis and Southern blotting. What step do you need to take next? A. Add ethanol B. Add restriction enzymes C. Add minisatellites D. Add radioactive probes
Add minisatellites. Hence, option C is correct.
What is Electrophoresis?Electrophoresis is a laboratory technique used to separate DNA, RNA or protein molecules based on their size and electrical charge.
You are a forensic scientist working on a murder case. You have taken the blood sample from the crime scene and put it through Electrophoresis and Southern blotting. you need to add minisatellites.
Hence, option C is correct.
Learn more about Electrophoresis here:
https://brainly.com/question/13949940
#SPJ2
How many electrons can the n = 4 shell hold? 8 16 32 64
Answer:
32Explanation
n = 4
Now,let's find the number of electrons:
[tex]2 {n}^{2} [/tex]
plug the value
[tex] = 2 \times {4}^{2} [/tex]
Evaluate the power
[tex] = 2 \times 16[/tex]
Multiply the numbers
[tex] = 32[/tex]
Hope this helps...
best regards
Electrons are the sub-particles present in atomic shells. The (Principal Quantum Number) n = 4 shell of the atom can hold 32 electrons in it. Thus, option c is correct.
What is Principal Quantum Number?Principal Quantum Number (n) is defined as the distance of the electron from the nucleus and its energy in the atom. It can also be said to know the position of the electron in the energy level along with the orbital size.
The Principle Quantum Number, n = 4 depicts the fourth shell or energy level of the atom that can hold a specific number of electrons in it.
The electrons present in the shell or the energy level are determined by,
2n²
Here, n = 4
Substituting the values above,
= 2 (4)²
= 2 (16)
= 32
Therefore, the n = 4 energy shell can contain 32 electrons.
Learn more about Principal Quantum Number here:
https://brainly.com/question/13312003
#SPJ6
what is heat energy in science
Answer:
Heat energy is the result of the movement of tiny particles called atoms, molecules or ions in solids, liquids and gases. Heat energy can be transferred from one object to another. the transfer or flow from one object to another is called heat.
hopefully this helped :3
Which metal will react spontaneously with Cu2+ (aq) at 25°C?
Hg
Mg
Ag
Au
Answer:
Mg
Explanation:
The standard reduction potentials are
E°/V
Au³⁺(aq ) + 3e⁻ ⟶ Au(s); 1.42
Hg²⁺(aq) + 2e⁻ ⟶ Hg(l); 0.85
Ag⁺(aq) + e⁻ ⟶ Ag(s); 0.80
Cu²⁺(aq) + 2e⁻ ⟶ Cu(s); 0.34
Mg2+(aq) + 2e- ⟶ Mg(s); -2.38
The more negative the standard reduction potential, the stronger the metal is as a reducing agent.
Mg is the only metal with a standard reduction potential lower than that of Cu, so
Only Mg will react spontaneously with Cu²⁺.
Answer:
B. Mg
Explanation:
Seawater is highly saline, which means it contains large amounts of dissolved salt. When seawater freezes and icebergs form, the water in the iceberg doesn’t take the salt with it. What effect will this phenomenon have on the concentration of salt in the water around the iceberg?
Answer:
Because the amount of liquid water decreases and the amount of dissolved salt remains constant, the concentration of salt in the liquid water around the iceberg will increase.
Explanation:
Answer:
Because the amount of liquid water decreases and the amount of dissolved salt remains constant, the concentration of salt in the liquid water around the iceberg will increase.
Explanation:
PLATO exact answer
Name the hydro carbon.... I really need your help guyz
Answer:
The given hydrocarbon is Butanol
how many different d orbits are within the 3d sublevel
Answer:
Its 5
Explanation:
Two samples of sodium chloride were decomposed into their constituent elements. One sample produced 2.84 g of sodium and 4.37 g of chlorine. Which of the following could be the results of the decomposition of the other sample, being consistent with the law of constant composition (also called the law of definite proportions or law of definite composition)?
a) 4.17 g of sodium and 3.75 g of chlorine
b) 4.17 g of sodium and 6.42 g of chlorine
c) 4.17 g of sodium and 1.05 g of chlorine
d) 4.17 g of sodium and 12.1 g of chlorine
Answer:
The correct answer is b) 4.17 g of sodium and 6.42 g of chlorine
Explanation:
According to the law of definite proportions a chemical compound is composed always by the same elements in the same proportions by mass. In this case, the proportion of the elements by mass will be 4.37 g of chlorine (Cl) per 2.84 g of sodium (Na):
4.37 Cl/2.84 g Na= 1.54
We can calculate the proportions of the results in order to see which is the correct:
a) 3.75 g Cl/4.17 g Na = 0.899
b) 6.42 g Cl/4.17 g Na = 1.539 ⇒ ≅1.54
c) 1.05 g Cl/4.17 g Na = 3.971
d) 12.1 g Cl/4.17 g Na = 2.901
The option in which the proportion Cl/Na is equal to 1.54 is option b
formula of sodium bicarbonate
please help me with this
Answer:
NaHCO₃
Explanation:
Sodium bicarbonate (baking soda) is a chemical compound with the formula NaHCO₃.
Explain how temperature and volume of a gas are related and use that to make a prediction about
how you can use this information to calculate absolute zero.
Answer:
See explanation
Explanation:
Charles law gives the relationship between volume and temperature of a gas. Charles law States that, the volume of a given mass of gas is directly proportional to its temperature at constant pressure.
Theoretically, it is assumed that when the absolute zero temperature has been achieved, the volume of any ideal gas will be found to be equal to zero. If the volume of the gas is zero, it now implies that all molecular motion will be stopped. This does not happen in real gases as all gases are found to condense to solids or liquids when this temperature is exceeded.
When volume is plotted against temperature, volume of the gas approaches zero at t = −273.15 °C, which is the x-intercept of the Charles law graph. Below this temperature, we can only get negative values of volume which does not exist hence, −273.15 °C is the lowest attainable temperature also known as the absolute zero.
If the external vapor pressure is 2.0 atm , what is the vapor pressure of the water at its boiling point?
Answer:
22
Explanation:
22
Which statement accurately describes a light-year
Answer:
B. distance light travels in a year
got it on edge :)
The statement which accurately and best describes a light-year is the total distance which light travels in a complete year
What is velocity of light?Velocity of light can simply be defined as that fundamental constant that represents the speed of electromagnetic radiation in a vacuum.
The velocity of light = 2.9979 × 10^10cm/s
So therefore, the statement which accurately and best describes a light-year is the distance which light travels in a complete year
Learn more about light-year:
https://brainly.com/question/1224192
#SPJ2
What would 12.47 rounded to 2 sig figs be?
Answer:
12
Explanation:
To get to this answer you have to look at the number first. So the given number is 12.47 and you need 2 sig figs.
To help you understand this more start off by underlining the first 2 numbers because 2 sig figs are needed. 12.47
Now you want to look at the number after the underlined (I bolded that number). 12.47
If the number is above 5 then you would round the previous number up by one but in this case it is 4 so you do not increase the number. Hence, you getting 12 as your final answer.
Hope this helped! Let me know if you have any questions.
True or False a. Sodium chloride is the main salt found in sea water. ……………………………………………………………………. b. Potassium bromide salt is not found in sea water ……………………………………………………………………. c. Both evaporation and electric conduction techniques prove that sea water contain the dissolved salts. …………………………………………………………………….. d. The amount of fresh water is greater than 5% of the total Earth water. …………………………………………………………………….. e. In water treatment process, filter membrane is used to remove fine particles and other impurities from water. …………………………………………………………………………....
Answer:
A is true NaCl
B is false K2Br
C is true
D false its only 0.03 percent
E is true
An element A reacts with water to form a compound B which is used in white washing. On exposure to air compound B forms C. The compound C on heating forms an oxide D which on treatment with water gives back B. Identify A, B and C and D, write the balanced chemical equations for the reactions involved.
Answer:
A- Ca
B- Ca(OH)2
C-CaCO3
D- CaO
Explanation:
Element A is calcium. Calcium reacts with water to form calcium hydroxide (compound B) as follows; Ca(s) + 2H2O(l) ----> Ca(OH)2(s) + H2(g).
When exposed to air, calcium hydroxide (compound B) forms calcium trioxocarbonate IV (CaCO3) which is compound C as follows;
Ca(OH)2(s) + CO2(g) -----> CaCO3(s) + H2O(l)
On heating compound C, the oxide, CaO (D) is formed as follows;
CaCO3(s) ------> CaO(s) + CO2(g)
This oxide reacts with water to yield B again as follows;
CaO(s) + H2O(l) ----> Ca(OH)2(s)
In heating and melting curves, what is the name of the heat associated with the solid-liquid phase? A. Heat of formation B. Heat of fusion C. Heat of sublimation D. Heat of vaporization
Answer:
C I believe not quite sure tho
In heating and melting curves, the name of the heat associated with the solid-liquid phase is Heat of fusion.
What is the Heat of fusion ?
The standard fusion enthalpy is the amount of thermal energy required for a single mole of a substance to change states from a solid to a liquid or vice versa is known as the heat of fusion or specific melting heat. The melting point is the temperature at which it takes place, and it is also known as the latent heat of fusion or the enthalpy change of fusion.The temperature of a liquid or solid goes down when thermal energy is taken away. The temperature rises when heat and energy are added. However, additional energy—the heat of fusion—is required at the melting point—the transition point between solid and liquid. The molecules of a substance need to become more organized in order to change from liquid to solid. They require the withdrawal of additional heat in order to maintain their solid state. In the opposite direction, additional heat is required to induce the disorder from the solid crystal to the liquid.The temperature of water as it freezes can be measured to observe the heat of fusion. When you place a closed container of room temperature water in a very cold environment, say 20 °C, the temperature will gradually fall until it is just below the freezing point. After that, the temperature rises and stays the same as the water crystallizes. The temperature will again fall steadily after it has completely frozen.The heat of fusion causes the temperature to stop falling at (or just below) the freezing point. Before the temperature can continue to fall, the energy from the heat of fusion must be removed—the liquid must transform into a solid.
To know more about heat of fusion check this:
brainly.com/question/2554334
#SPJ2
Why are the oxidation and reduction half-reactions separated in an
electrochemical cell?
Answer:
It makes the current viable enough to pass through an exterior wire.Explanation:
Electrochemical cells primarily comprise of two half-cells. These half-cells assist in isolating the oxidation and reduction half-reactions. These two reactions are linked by a wire which allows the current to move from one edge to the other. The oxidation at the anode and the reduction take place at the cathode and the addition of a salt bridge helps in completing the circuit and permits the current to flow and leads to the generation of electricity.
The solubility product constant at 25°C for AgI(s) in water has the value 8.3 × 10–17. Calculate ∆Grxn at 25°C for the process AgI(s) <--> Ag+(aq) + I– (aq) where [Ag+] = 9.1 × 10–9 and [I–] = 9.1 × 10–9. –91.7 kJ/mol +91.7 kJ/mol 0.0 kJ/mol –4.4 kJ/mol +4.4 kJ/mol
Answer:
+91.7 KJmol-1
Explanation:
Recall that ∆G= -RTlnK
Since ∆G in this case is ∆Grxn and K is the Ksp
Note that the Ksp is the solubility product (as shown by the reaction equation)
∆Grxn is the change in free energy for the reaction, in this case the ionization of the silver iodide into silver and iodide ions.
R= 8.314JK-1 and T =25°C +273 = 298 K (the centigrade temperature must be appropriately converted to its corresponding absolute absolute before proceeding with the calculation)
Hence we can substitute values accordingly;
∆Grxn = -(8.314 × 298 × ln 8.3×10^-17)
∆Grxn = +91.7 KJmol-1
What are canal rays ?
Answer:
Channel rays or anode rays are a historical name for positive ion beams, due to their first embodiment. They were indeed observed experimentally for the first time by a German physicist, Eugen Goldstein, in 1886.
Explanation:
what will happen if a candle will be covered with an inverted jar filled will nitrogen
Answer:
The flame will burn out
Explanation:
The oxygen will be kept out of the jar, without oxygen the flame cannot last long. The flame will eventually burn out. Nitrogen gas has no role to play in the burning. Nitrogen slows down the burning rate.
Which of the following increases the average kinetic energy of colliding particles? A. adding a catalyst B. increasing the temperature C. increasing the reactant concentration D. increasing the surface area
The average kinetic energy of colliding particles can be increased by increasing temperature.
B.
Answer:
B
Explanation:
Increasing the Temperature
hello:)!! for the preparation of salts , I don’t really understand the part where acids react with insoluble bases. do I just memorise it? :) thanks!
Answer:
I think if u will clear your topic it would be more helpful.
But if u r unable to do it, then u can just memorise it.
See, i will try to help u.
Salts are formed when acids react with bases.
and this reaction is called neutralisation reaction.
e.g. HCl+NaOH=NaCl+H2O.
It is very easy.
Other examples:
H2SO4+Mg(OH)2=MgSO4+2H2O.
There may be some other reactant with acid like u have mentioned above.
hope it helps u....
plz mark as brainliest...
Label the chemical equation.
2 Mg(s) + O2(g) → 2 MgO(s)
Label the chemical equation.
2 Mg(s) + O2(g) → 2 MgO(s)
Answer:
Kindly check Explanation
Explanation:
Given the chemical equation:
2 Mg(s) + O2(g) → 2 MgO(s)
2 molecules of Magnesium + Oxygen gas (Reactant)
→ ( yield)
2 molecules of magnesium oxide (product)
2 in Mg and MgO (coefficients)
2 in Oxygen gas (subscript)
Solid (s) - physical state of Reactant Mg
Gas (g) - physical state of Reactant O2
Solid (s) - physical state of product 2MgO
A stone bead and an iron bead are dropped into a cup of water. They both sink to the bottom of the cup. What can be said about these beads?Immersive Reader
Answer:
Both have densities greater than that of water
Explanation:
The ability of objects to either float or sink in a liquid depends on their relative densities.
If an object is denser than a liquid it will completely sink in it, but if the density of the object is less than that of the liquid, it will sink until the weight of liquid displaced is equal to the weight of the object, then it will finally float in that liquid.
In the case of the stone bead and iron beads dropped into a cup of water, hey both sank to the bottom because they are denser than water.
The instruction booklet for your pressure cooker indicates that its highest setting is 11.5 psi . You know that standard atmospheric pressure is 14.7 psi, so the booklet must mean 11.5 psi above atmospheric pressure. At what temperature in degrees Celsius will your food cook in this pressure cooker set on "high"
Answer:
16.83°
Explanation:
The computation of temperature in degrees is shown below:
For this we need to applied the combination of the Clasius Clapyeron equation which is
[tex]ln(\frac{P_2}{P_1}) = \frac{-\Delta Hvap}{R} \times (\frac{1}{T_2}- \frac{1}{T_1})[/tex]
Where
P_2 and P_1 represents the pressure of vapor at point 1 and 2
dH = Here we use J/mol
R = 8.314 J/mol K
T1 and T2 represent the temperature of Saturation temperature for point 1 and 2
Now
we have to change the negative signs
i.e
[tex]ln(\frac{P_2}{P_1}) = \frac{\Delta Hvap}{R} \times (\frac{1}{T_1}- \frac{1}{T_2})[/tex]
As we know that
dHvap for water = 40.67 kJ/mol
T1 = 373 K,
T2 = x
P1 = 14.7 psi;
P2 = 11.2 + 14.7 = 25.9 psi
Now put the values to the above formula
So,
[tex]ln (\frac{25.9}{14.7}) = \frac{40670}{8.314} \times (\frac{1}{373}- \frac{1}{T_2})\\\\T_2 = - (ln (\frac{25.9}{14.7})\times \frac{8.314}{40670} - \frac{1}{373})^{-1}[/tex]
After solving this
T_2 = 389.836K
T_2 = 389.836 - 273
T_2 = 116.836 °C
Therefore by 16.83°, it becomes higher
anne added a sample of hydrochloric acid to water and determined the pH to be 1.79. what is the poH of the solution?
Answer: 12.21
Explanation:
It is well known that the sum of pH + pOH = 14.
To get the pOH of the solution, we subtract 1.79 from 14.
pH + pOH = 14
pOH = 14 - 1.79 = 12.21
pOH = 12.21
what are the property of electrons
Answer:
basically an atom consist of electons and protrons .
electrons have a negative charge and in a circut the charge of electorns is more.
Answer:
listed below.
Explanation:
Few properties of electrons include:
- Electrons are subatomic particles with an electric charge of -1.
- Electrons have mass of approximately 1/1836 that of the proton.
- Electrons revolve around the nucleus of the atom.
- Electrons spin around their own axis.
Who is john Dalton ?
Answer:
He is a English chemist physicist and meteorologist. He is best known for the atomic theory
Answer:
John Dalton was a scientist.
Explanation: