Explanation:
Heat transfer by radiation tends to be minimal in many everyday instances. This is in part, due to the 4th power exponentiation of the heat transfer equation that governs radiative heat transfer.
For instance, a bar of metal of 75 ºF will interact with your body, from a distance, when your body is at 98 ºF. But the temperature difference of 14 ºF will be so low, that it is difficult to feel or detect. However, if that bar was heated to 120º F and set close to you, you may begin to feel the heat from radiation. Then, if the bar was heated to the point that it began to glow red, several hundred degrees, not only would you feel it, but it may make you uncomfortably hot very quickly. If it was then heated to being white hot, you would almost certainly be burned by it, not by touching it, but simply by the radiative heat transfer. Again, its the 4th power exponent that really makes radiative heat transfer a powerful force when the temperature increases to a high level.
Another example from a text that I once used set an example of a person in a room with their body temperature at 98 ºF. In one case, the walls of the room surrounding the body are said to be 50º F, but in the other case, the walls are said to be 100º F. In both cases, the air in the room is said to be 75ºF. The question is asked: why is the person colder in the room with 50 ºF walls, when the air is the same temperature in both cases.
The answer is that the 100 ºF walls are acting to slightly warm the body, whereas the 50º F walls are actually taking heat away from the body by way of radiative heat transfer. You can do the equations to see exactly how much the different temperatures of the walls will effect this situation.
One final example - if you look into a thermos, you will see a highly reflective liner inside of the thermos. This is a radiant barrier, and it is put into the thermos to keep the liquid inside from losing heat by way of radiation. The reflective film will transfer back most of the heat that would otherwise be lost by radiating to the outer surface of the thermos, after which it would conduct through the side of the thermos. So a thermos provides a good example of a solution for heat transfer in the form of radiation.
When a chemical reaction occurs, what happens to the atoms of the two substances?
Answer:
In a chemical reaction, only the atoms present in the reactants can end up in the products. No new atoms are created, and no atoms are destroyed. In a chemical reaction, reactants contact each other, bonds between atoms in the reactants are broken, and atoms rearrange and form new bonds to make the products.
Explanation:
What is the scientific name of hydrogen -2 and hydrogen -3.
Answer:
Hydrogen 2 is called deuterium, Hydrogen 3 is called Tritium
Explanation:
Hydrogen is the only element whose isotopes have different names in common use today: the 2H (or hydrogen-2) isotope is deuterium and the 3H (or hydrogen-3) isotope is tritium.
4. What is the maximum no. of electrons that can be associated with the following set of
quantum numbers?
n=4, l=1, m=-1
a) 10
b) 6
d) 2
c) 4
Answer:
d) 2
Explanation:
We are given;
n = 4, l = 1, m = -1
We can tell that is is an orbital with sub shell as 3P.
Now, from Paul's exclusion principle, each orbital will have maximum of 2 electrons of each π with a spin of +½ and -½.
Since the maximum is seen to be 2, then option D is correct.
When a baseball bat hits a baseball, what happens to the energy?
completo ancur
Answer: the baseball bat transfor its energy in the ball.
Explanation: you hit it with one and find out and tell me what you think what happen.
What volume of 0.130 M HCl is required for the complete neutralization of 1.30 g of NaHCO3 (sodium bicarbonate)?
Answer: Volume required is 0.115 L or 115 ml
Explanation:
moles of [tex]NaHCO_3[/tex] = [tex]\frac{\text {given mass}}{\text {Molar mass}}=\frac{1.30g}{84g/mol}=0.015mol[/tex]
The balanced chemical equation is:
[tex]HCl+NaHCO_3\rightarrow NaCl+H_2CO_3[/tex]
1 mole of [tex]NaHCO_3[/tex] requires = 1 mole of HCl
Thus 0.015 mol of [tex]NaHCO_3[/tex] requires = [tex]\frac{1}{1}\times 0.015=0.015[/tex] mole of HCl
Molarity of a solution is defined as the number of moles of solute dissolved per liter of the solution.
[tex]Molarity=\frac{n}{V_s}[/tex]
where,
n = moles of solute
[tex]V_s[/tex] = volume of solution in L
[tex]0.130=\frac{0..015}{V_s}[/tex]
[tex]V_s=0.115L[/tex]
Thus volume required is 0.115 l or 115 ml
If 25.00 mL of 6.00 M HCl is transferred by pipet into a volumetric flask and diluted to 5.00 L, what is the molarity of the diluted HCl?
Answer:
0.03 M
Explanation:
The computation of the molarity of the diluted HCI is given below:
As we know that
(M1) × (V1) = (M2) × (V2)
Now
(M2) = {(M1) × (V1)} ÷ (V2)
or
Molarity of the diluted HCl,(M2) is
= {6 × 25} ÷ 5000
= 0.03 M
A compound or material formed by a chemical reaction is know as the of the reaction
Answer:
reactants
Explanation:
please give brainlist
Answer:
Reactant
Explanation:
Which factors play a role in creating ocean waves?
Choose all answers that are correct.
wind duration
wind speed
wind change
wind elevation
wind direction
wind fetch
Answer:
1. Wind speed
2. Wind change
3. Wind elevation
4. Wind direction
Answer:
For k12 its::
Explanation:
wind direction
wind speed
wind fetch
wind duration
Yw guys! ^^
Question 1 (0.25 points)
What is the name for the land area where all rain runs downhill to a certain point?
O watershed
O collection
O estuary
O ocean
In an ecosystem , watershed is the name for the land area where all rain runs downhill to a certain point.
What is an ecosystem?Ecosystem is defined as a system which consists of all living organisms and the physical components with which the living beings interact. The abiotic and biotic components are linked to each other through nutrient cycles and flow of energy.
Energy enters the system through the process of photosynthesis .Animals play an important role in transfer of energy as they feed on each other.As a result of this transfer of matter and energy takes place through the system .Living organisms also influence the quantity of biomass present.By decomposition of dead plants and animals by microbes nutrients are released back in to the soil.
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What are the four types of human pathogens that
can cause infectious disease?
Answer:
Viruses, bacteria, fungi, and parasites.
Explanation:
hope this helps and is right :)
[50 Points] In the experiment below, Beaker 1 contains 12.0 M HCl. Each subsequent beaker is diluted by 50%. What is the [OH-] in Beaker 6?
Answer:
2.67x10⁻¹⁴M = [OH-]
Explanation:
To solve this question we need first to find the HCl concentration of the beaker 6. Then, using:
Kw = [OH-][H+]
Where Kw = 1x10⁻¹⁴
[OH-] is our incognite
[H+] is = [HCl]
Beaker 2 = 12.0M / 2 = 6.0M
Beaker 3 = 6.0M / 2 = 3.0M
Beaker 4 = 3.0M / 2 = 1.5M
Beaker 5 = 1.5M / 2 = 0.75M
Beaker 6 = 0.75M / 2 = 0.375M
HCl = 0.375M = [H+]
1x10⁻¹⁴ / [H+] = [OH-]
1x10⁻¹⁴ / 0.375M = 2.67x10⁻¹⁴M
2.67x10⁻¹⁴M = [OH-]how many electrons does chlorine need to gain to become an ion? will it become positively charged cation or negatively charged anion?
complete the equation C14H30 = ________ + C7H14
Answer:
C14H30 -----> C7H14 + C2H4 +C5H10
Explanation:
Tengo que resolver con procedimiento
1. Un automóvil viaja a una velocidad de 100 Km/h durante dos horas. Calcular la distancia recorrida.
2. Un automóvil viaja a una velocidad de 68 Km/h durante tres horas. Calcular la distancia recorrida.
3. Un auto recorre 154 Km en dos horas. ¿Cuál fue su velocidad?
4. Un auto recorre 1500 Km, si lo hace a una velocidad de 70 Km/h, ¿cuánto tardo en hacerlo?.
Answer:
Distance = 200 km
Distance = 204 km
Speed = 77 km/h
Time = 21.42 h
Explanation:
Given:
A.
Speed = 100 km/h , Time = 2 h
Find:
Distance
B.
Speed = 68 km/h , Time = 3 h
Find:
Distance
C.
Distance = 154 km , Time = 2 h
Find:
Speed
D.
Distance = 1500 km speed = 70 km/h
Find:
Time
Computation:
Speed = distance / time
A.
Distance = 100 x 2
Distance = 200 km
B.
Distance = 68 x 3
Distance = 204 km
C.
Speed = 154 / 2
Speed = 77 km/h
D.
Time = 1500 / 70
Time = 21.42 h
Consider the reaction: S(s) O2(g)SO2(g) Write the equilibrium constant for this reaction in terms of the equilibrium constants, Ka and Kb, for reactions a and b below: a.) 2 S(s) 3 O2(g) 2 SO3(g) Ka b.) SO2(g) 1/2 O2(g) SO3(g) Kb
Answer:
[tex]Ka=\frac{[SO_3]^2}{[O_2]^3} \\\\Kb=\frac{[SO_3]^3}{[SO_2][O_2]^{1/2}}[/tex]
Explanation:
Hello!
In this case, according to the reactions:
a.) 2 S(s) 3 O2(g) ⇔ 2 SO3(g) Ka
b.) SO2(g) + 1/2 O2(g) ⇔ SO3(g) Kb
Thus, according to the law of mass action, we can write Ka and Kb as follows:
[tex]Ka=\frac{[SO_3]^2}{[O_2]^3} \\\\Kb=\frac{[SO_3]^3}{[SO_2][O_2]^{1/2}}[/tex]
Whereas solid carbon is not inserted in the equilibrium expression.
Best regards!
plz need help right away !
Explanation:
1 mole = 6.02 x 10^23 atoms (Avogadro’s number)
Step 1) Determine how many grams of a substance are in the problem
Step 2) Find the amount of grams in 1 mole of the substance
3) Multiply step one by step two
Billy and Susie heat a 78.9 g sample of Unobtanium at 18.0C. Using a lab burner, they burn propane and the unobtanium absorbs 13,240 J of heat untill the temperature reaches the melting point 109C. what is the specific heat of unobtanium
Answer:
1.8 J/g·°C (2 sig.figs. per ΔT)
Explanation:
Given:
mass (m) = 78.9 grams
specific heat (c) = ?
Temp. Change (ΔT) = 109°C - 18°C = 91°C
Heat flow (q) = 13,240 Joules
q = m·c·ΔT => c = q/m·ΔT
∴c = 13,240J / 78.9g·91°C = 1.844 J/g·°C ≅ 1.8 J/g·°C (2 sig.figs. per ΔT)
A chemistry graduate student is studying the rate of this reaction:
NH4OH(aq)→NH3(aq)+H2O(aq)
She fills a reaction vessel with and measures its concentration as the reaction proceeds:
Time (minutes) NH4OH
0 0.200M
1.0 0.0895M
2.0 0.577M
3.0 0.0426M
4.0 0.0337M
Use this data to answer the following questions.
a. Write the rate law for this reaction.
b. Calculate the value of the rate constant.
Answer:
Rate = k[NH₄OH]²
k = 6.17
Explanation:
We have concentrations of NH₄OH along with the given times. To determine the rate law of the reaction we need to determine first the order of reaction. This reaction can be order zero, first or second order. The expressions for each are the following:
Zero order:
k = [A₀] - [A] / t
First order:
k = 1/t * ln([A₀]/[A])
Second order:
k = (1/t) * (1/[A₀] - 1/[A])
And from here, the next part is easier. We just need to determine hat order is, calculating the value of k at two different times. If the value of k is constant, then we can say that the reaction is of that order.
Let's suppose its order zero (t = 1 and t = 2, [A₀] = 0.200 M):
k1 = 0.2 - 0.0895 / 1 = 0.1105
k2 = 0.2 - 0.577 / 2 = -0.1885
From this results we can conclude it's not zero order.
Let's suppose its order 1:
k1 = ln(0.2/0.0895) / 1 = 0.8041
k2 = ln(0.2/0.577) / 2 = 0.1733
It's not first order either, so we can conclude that this reaction is of 2nd order and the rate law would be:
Rate = k[NH₄OH]²Now that we know it's a second order reaction, we can determine the value of k using its expression:
k = (1/t) (1/[A] - 1/[A₀])
k = ln(1/0.0895 - 1/0.2) (1/1)
k = 6.17
And to confirm this value, let's calculate k for t = 2 s
k = (1/2) (1/0.0577 - 1/0.2)
k = 6.17The value is constant, so this is the true value of k.
Hope this helps
A certain liquid X has a normal boiling point of 129.90°C and a boiling point elevation constant =Kb= 1.67°C·kgmol^−1. Calculate the boiling point of a solution made of 90.g of iron(III) chloride (FeCl3) dissolved in 650.g of X.
Answer:
Boiling T° of solution = 135.6°C
Explanation:
Formula for elevation boiling point is:
ΔT = Kb . m . i
ΔT = Boiling point of solution - Boiling point of pure solvent
Kb = Boiling point elevation constant
m = molality → moles of solute in 1kg of solvent
i = numbers of ions dissolved
FeCl₃ → Fe³⁺ + 3Cl⁻
In the dissociation of the ionic salt, we determined 4 moles of ions dissolved.
3 for chlorides and 1 for iron. Then i = 4
m → We convert the mass of solute to moles:
90 g . 1mol / 162.2g = 0.555 moles
650 g of solvent = 0.650 kg of solvent
m = 0.555 mol/0.650kg → 0.85
We replace data at formula
Boiling T° of solution - 129.90°C = 1.67°C . kg/mol . 0.85 mol/kg . 4
Boiling T° of solution = 1.67°C . kg/mol . 0.85 mol/kg . 4 + 129.90°C
Boiling T° of solution = 135.6°C
What is the product of the first beta decay in this series?
A)
AC-227
B)
Ac 228
Ra-227
D
Rn 224
Answer:
B)
Explanation:
In beta decay the nucleus loses a neutron and gains a proton. The mass therefore remains constant but the atomic number increases by one.
How many molecules are in 228.7 grams of KBr?
Answer:
the answer is 119.0023 grams
which one of the following a compounds a.sugar b.rock salt c.iron d.alloy
which one of the following a
compound ?
a.sugar c.alloy
brock salt d.iron
Answer:
a
Explanation:
sugar is composed of different elements combined in a manner form
A substance that cannot be broken down into another substance by chemical or physical means is called a
Answer:
A substance that cannot be broken down into another substance by chemical or physical means is called an Element
The average adult heart pumps about 84./mLs of blood at 72 beats per minute. Suppose you need to calculate how long it would take the average heart to circulate 1700.mL of blood. Set the math up.
Answer:
1700 mL / 84 mLs
Explanation:
Given that:
Volume of blood pumped per minute = 84 /mLs
Time it takes to circulate 1700 mL of blood :
Time taken = Volume of blood circulate / Rate
Hence, to circulate 1700 mL of blood :
Time taken = 1700 mL / 84 mLs
Describe what an Ionic Substance is....
Answer:
Ionic Substance is....
Explanation:
In chemistry, an ionic compound is a chemical compound composed of ions held together by electrostatic forces termed ionic bonding. The compound is neutral overall, but consists of positively charged ions called cations and negatively charged ions called anions.
How can people conserve water at home?
Answer:
Turning off the water while brushing teeth, watching shower time.
Explanation:
Answer:
Take shorter showers.
Install water-saving shower heads or flow restrictors.
Turn off the water while brushing your teeth.
Turn off the water while shaving.
Explanation:
have a nice day
Select the statement that best describes components of complete and incomplete metamorphosis. (2 points)
a. During incomplete metamorphosis, the nymph molts its exoskeleton. During complete metamorphosis, the larva forms a chrysalis or cocoon.
Selected:b. During incomplete metamorphosis, the pupa molts its exoskeleton. During complete metamorphosis, the nymph wraps itself in a chrysalis.This answer is incorrect.
c. Incomplete and complete metamorphosis both have four major stages.
d. Incomplete and complete metamorphosis both have three major stages. btw b was wrong
Answer:
a. During incomplete metamorphosis, the nymph molts its exoskeleton. During complete metamorphosis, the larva forms a chrysalis or cocoon.
Explanation:
The first stage of incomplete metamorphosis is the egg. During this time, the insect will hatch into a form called a nymph. The nymph is basically a small version of the adult insect. This is very similar to how a child looks like his or her parents.
The correct statement that describes components of complete and incomplete metamorphosis is: d. Incomplete and complete metamorphosis both have three major stages.
What is metamorphosis ?Metamorphosis is a biological process that some animals undergo to transform from one developmental stage to another, typically from a juvenile form to an adult form. This process involves a series of physical and physiological changes that can be dramatic and even complete.
Incomplete metamorphosis consists of three stages: egg, nymph, and adult. The nymph hatches from the egg and looks similar to the adult but lacks wings and reproductive organs. The nymph molts its exoskeleton several times and gradually develops into an adult.
Complete metamorphosis also consists of three stages: egg, larva, pupa, and adult. The larva hatches from the egg and looks completely different from the adult, often worm-like in appearance. The larva undergoes a series of molts and grows larger, then forms a pupa or chrysalis. Inside the pupa or chrysalis, the larva undergoes a complete transformation and emerges as an adult.
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How are people and the landscape impacted by earthquake?
they are impacted because people loose their home due to the wreckage that has happend and landscapes are ruined due to landslides
Answer:
Well the landscape is torn up, it goes through quite a bit of damage. the plants, animals, and water are all affected by it. when a earth quake hits it destroyes most everything, houses fall into the ground and are destroyed, people die. Earthquakes destry electrical wires and many other things
Explanation:
Sorry I did not answer it full, but you can look it up online.
Given the following:
Measurement Reaction 1 (Mg + HCl)
Mass of HCl (g) 100.50
Mass of solid (g) 0.20
Total mass of reactants, m (g) (add the masses above) 100.70
Initial Temperature (°C) 22.5
Temperature furthest from initial temperature(°C) 31.3
∆T(°C) Subtract the two temperatures above) 8.8
Given Reaction 1: Mg(s) + 2HCl(aq) ⟶ MgCl2(aq) + H2(g)
What is the ∆H (kJ/mol)?
Answer:
∆H = - 450 kJ/mol
Explanation:
You can calculate the change in enthalpy provided we have the heat of solution (q). That would be the only approach to this problem. But this approach is only possible if we have a specific set-up; we would have to use a calorimeter. So then the reactants are taken as the system, and water as the surroundings. When calculating q, the heat of the solution, we take 4.18. Remember that heat is flowing from the reaction mixture, to the water, from the system to surroundings, so it's exothermic and ∆H = negative:
Attempt 2
Four marbles are made of different metals. Each marble has the same mass, but a different volume. The density of each
metal is given in the table.
Metal
Density (g/mL)
aluminum
2.70
silver
10.5
rhenium
20.8
nickel
8.90
Place the marbles in order from largest to smallest.
Largest
The order of marbles can be Aluminum, Nickel, Silver, and Rhenium.
What is volume?If volume is the amount of three-dimensional space contained by a closed surface, such as the amount of space within a given cube, cylinder, or other three-dimensional shape.
Liquid volume is a way to measure an amount of liquid by describing how much three-dimensional space it occupies.
The mass of something is the amount of stuff it is made of. The volume of an object is the amount of space it usually takes up.
Density provides an easy way to calculate a body's mass from its volume or vice versa.
The mass is equal to the volume multiplied by the density (M = Vd), and the volume is equal to the mass divided by the density (V = M/d).
As per the density given, the volume of aluminum can be 1.11mL, Silver is 0.286mL, Rhenium is 0.144mL, Nickel is 0.337mL.
Thus, the order from largest to smallest will be Aluminum, Nickel, Silver, and Rhenium.
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