Answer:
Explanation:
Here we'll use our formula for specific heat, Q=mcΔT.
Q= Heat (Joules), m=mass (g), c=specific heat
ΔT= (final temperature - initial temperature)
When we add a heated piece of metal in water at a lower temperature, the metal will lose heat and the water will absorb that heat. Over time they will eventually reach an equilibrium, here we have it at 21.9 C. If you recall in thermodynamics, , when we lose heat it is exothermic and the values of exothermic reactions are negative, and the values of endothermic reactions are positive. So we can say the heat of the metal is exothermic and releasing heat into the water until they reach equilibrium, thus they are equal. Keeping in mind Q= heat,
-Q metal = Q water.
We can expand this equation to -mcΔT= mcΔT.
Our equation reflects what is happening to the metal and the water.
Before we start, it might be helpful to remember that the
c=specific heat of water= 4.186 J/g C
Let's plug in what we know and solve for c=specific heat of metal. I'll start with the left side then go to the right side.
-(23.9g)(c)(29.9-97.8) = (52.4g)(4.184)(29.9 - 21.9)
-(23.9gc)(29.9-97.8) = (52.4g)(4.184)(29.9 - 21.9)
-(23.9g)(c)(-67.9) = (52.4g)(4.184)(29.9 - 21.9)
1623c = (52.4g)(4.184)(29.9 - 21.9)
1623c = (52.4g)(4.184)(8)
1623c = 1754
c= [tex]\frac{1754}{1623}[/tex]
c= 1.08
This means it takes less heat to raise the temperature of the piece of metal ( in comparison to the water, which require more ).
Select all the correct answers.
Which statements demonstrate scientific research bias?
Jennifer studied the most convenient sample instead of obtaining a sample that better represented the entire population.
Tyler's conclusion was supported by his data, but it did not agree with his hypothesis.
Manny was presented with several possible research topics, and he chose the one he found most interesting.
Ellie carried out the same experiment four times, and she obtained the same result every time.
Brad expected a certain result from his experiment, so he interpreted his data in a way consistent with that result.
Answer:
1. Jennifer
Jennifer tried to cut corners and exclude a chunk of people from the population, making her results biased.
2. Brad
Brad was just seeing what he wanted to see, instead of facing the results of his experiment, which makes him scientifically biased. It's known as 'cherry-picking' informally.
Explanation:
Why are the rest not biased?
1. Tyler
You don't need your results and conclusion to agree with your hypothesis. A hypothesis is just your guess, it's not absolute and doesn't demonstrate bias if it doesn't agree with your conclusion.
2. Manny
He simply chose a topic he was interested in. It would be a different story if he already had a topic, but only chose information that agreed with his hypothesis, neglecting other pieces of information.
3. Ellie
This demonstrates no bias. She carried out an experiment and, according to experimental data, received the same results every time. She did not purposefully alter them to make them what she wanted to see.
Answer:
1. Jennifer
Jennifer tried to cut corners and exclude a chunk of people from the population, making her results biased.
2. Brad
Brad was just seeing what he wanted to see, instead of facing the results of his experiment, which makes him scientifically biased. It's known as 'cherry-picking' informally.
Explanation:
A sample of polonium-210 has an initial mass of 390 milligrams (mg). If the half-life of polonium-210 is 36 days, how many mg of the sample remains after 72 days?
A.
392 mg
B.
195 mg
C.
97.5 mg
D.
48.75 mg
Answer:
C
Explanation:
I got this question right on my test.
Which of the following has the largest mass of carbon per gram?
H₂CO₃
CH₃CO₂H
CH₃OH
CH₃CH₂OH
Answer:
ch3
Explanation:
WHAT IS A ROCK?
Please put the answer below
DO ITTT NOWWWWWWWWWWWWWW
|
\/
how many liters of N2 gas is needed to produce 500 L NH3?
4 NH3 (g) + 7 O2 (g) 4 NO2 (g) + 6 H2O (g)
The combustion of 28.8 g of ammonia consumes __________ g of oxygen.
Answer:
21
Explanation:
Air trapped in a cylinder fitted with a piston occupies 142.8 mL at 0.97 kPa pressure.
What is the new volume of air when the pressure is increased to 1.5 kPa by applying force
to the piston?
Answer:
92.344mL
Explanation:
acording to boyle's law that PV=constant then P1V1=P2V2
Name the part in red:
H2 + O2 -> H2O
Answer:subscript
Explanation:
What dosage in grams per kilogram of body weight does a 134 lb woman receive if she takes two 275 mg tablets of penicillin?
How many 150. mg tablets should a 31 lb child take to receive the same dosage?
Answer:
The dosage is 0.0906 g/kgThe child should take 8.5 tablets to receive the same dosageExplanation:
First we convert 134 lb into kg:
1 lb = 0.453 kg134 lb * [tex]\frac{0.453kg}{1lb}[/tex] = 60.702 kgThen we convert 275 mg into g:
1000 mg = 1 g275 mg * [tex]\frac{1g}{1000mg}[/tex] = 0.275 gNow we can calculate the dosage in grams per kilogram of body weight, keeping in mind that two tablets are consumed:
(0.275 g) * 2 / 60.702 kg = 0.0906 g/kgAs for the second part, first we convert 31 lb into kg:
31 lb * [tex]\frac{0.453 kg}{1lb}[/tex] = 14.043 kgNow we calculate how many penicillin grams should be consumed:
14.043 kg * 0.0906 g/kg = 1.27 gWe convert 1.27 g of penicilin into mg:
1.27 g * 1000 = 1270 mgFinally we calculate how many 150 mg tables should be taken:
1270 mg / 150 mg = 8.5 tabletsWhich gland would most likely have an issue with maintaining the breakdown of food?
the thyroid
the thymus
the pancreas
the ovaries
Answer:
OKAY EVERYONE STOP SAYING PANCREAS THATS WRONG
Explanation:
It is actually thyroid
Soil comes in different colors.
Answer: yes they come in different colors.
Explanation:
Most shades of soil is mostly black,brown,red,gray,and white the color of soil and other properties including texture, structure, and consistency are used to distinguish and identify soil.
The bullet train was traveling at a speed of 200mi/hr for 2 hours. What
was the total distance traveled? *
O 100mi
O 01mi
O 40mi
O 400mi
Answer:
Distance is speed x time
So 200 x 2 =400mi
Which agent of erosion is probably at work in the area
describe two sources of energy and explain how they work
please help me (50points)
Solar energy:-
In this way the energy generated through sun light with the help of solar panels and to be used in many works.
Wind energy:-
This is generated by moving turbines with windmills .It is used to create electric energy
The frequency of a wave does not change as it passes from one medium to another.
What will most likely happen if a light wave moves from the air into a solid?
The wavelength of the light wave will increase.
The speed of the light wave will decrease.
The wavelength of the light wave will remain the same.
The speed of the light wave will remain the same.
(in subject a put chemistry cause there was no science, the subject is science)
Answer:
it will decrease
Explanation:
on test. have a nice day
Answer:
I think it is c
Explanation:
The number of protons in an atom is known as its atomic
For the gaseous reaction below, the Kc value is 3.67. What is the Kp value at the same temperature? CO2 + H2 = CO + H20
Answer:
3.67
Explanation:
Step 1: Write the balanced equation
CO₂(g) + H₂(g) = CO(g) + H₂O(g)
Step 2: Calculate the value of the pressure equilibrium constant (Kp)
The concentration equilibrium constant (Kc) is 3.67.
We can calculate the value of the pressure equilibrium constant using the following expression.
[tex]Kp = Kc \times (R \times T)^{\Delta n(g)}[/tex]
where,
R: ideal gas constant
T: absolute temperature
Δn(g): moles of gaseous products - moles of gaseous reactants
Δn(g) = 2 mol - 2 mol = 0
Then,
Kp = Kc × (R × T)⁰ = Kc = 3.67
Using your freshly made 5M stock aqueous solution of NaCl and your 10% aqueous stock of SDS, you find a prepackaged bottle of 1M Tris-Hcl (aqueous solution) along with a 95% solution of liquid NP-40 in a bottle. Using these stock reagents calculate the amount needed for the following final concentrations for each reagent as well as the final volume of water needed to obtain:
Total Final volume of 500 mL
Final Concentrations:
150 mM NaCl
50 mM Tris-HCl
1% NP-40 .
1% SDS
Answer:
1. Volume of stock required = 15 mL
Volume of water required = 485 mL
2. Volume of stock required = 5 mL
Volume of water required = 495 mL
3. Volume of stock required = 5.30 mL
Volume of water required = 494.70 mL
4. Volume of stock required = 50 mL
Volume of water required = 450 mL
Explanation:
Using the dilution formula C₁V₁ = C₂V₂
Where C₁ = initial concentration; C₂ = final concentration; V₁ = initial volume; V₂ = final volume
1. C₁ = 5 M NaCl, C₂ = 150 mM NaCl = 0.15 M NaCl
V₁ = ?; V₂ = 500 mL
V₁ = C₂V₂/C₁
V₁ = 0.15 × 500/ 5 = 15 mL
Volume of stock required = 15 mL
Volume of water required = 500 mL - 15 mL
Volume of water required = 485 mL
2. C₁ = 1 M Tris-HCl, C₂ = 50 mM Tris-HCl = 0.05 M Tris-HCl
V₁ = ?; V₂ = 500 mL
V₁ = C₂V₂/C₁
V₁ = 0.05 × 500/ 5 = 5 mL
Volume of stock required = 5 mL
Volume of water required = 500 mL - 5 mL
Volume of water required = 495 mL
3. C₁ = 95% NP-40, C₂ = 1% NP-40
V₁ = ?; V₂ = 500 mL
V₁ = C₂V₂/C₁
V₁ = 1 × 500/ 95 = 5.30 mL
Volume of stock required = 5.30 mL
Volume of water required = 500 mL - 5.30 mL
Volume of water required = 494.70 mL
4. C₁ = 1% SDS, C₂ = 10% SDS
V₁ = ?; V₂ = 500 mL
V₁ = C₂V₂/C₁
V₁ = 1 × 500/ 10 = 50 mL
Volume of stock required = 50 mL
Volume of water required = 500 mL - 50 mL
Volume of water required = 450 mL
What is the difference between chemical change and physical change
Answer:
In a physical change the appearance or form of the matter changes but the kind of matter in the substance does not. However in a chemical change, the kind of matter changes and at least one new substance with new properties is formed.
Cuo
+ H2 → → Cu + + H20
colorless
water
black
powder
reddish
solid
gas
vapor
Explanation:
because there is 2 hydrogen atoms in the reactions side of the equation (you can tell because the H has a 2 in the subscript) you have to have 2 hydrogen atoms in the reactants side to help balance out the equation. and since the copper and oxygen atoms are already balanced there is no coefficient needed.
Calculate the volume, in milliliters, for the following:
.850 mol of NaNO3, from a .500 M NaNO3 solution
30.0 g of LiOH from a 2.70 M LiOH solution
Answer: The volume for 0.850 mol of [tex]NaNO_{3}[/tex] from a [tex]NaNO_{3}[/tex] solution is 1700 mL.
The volume of 30.0 g of LiOH from a 2.70 M LiOH solution is 464 mL.
Explanation:
Molarity is the number of moles of solute present in a liter of solution.
As given moles of [tex]NaNO_{3}[/tex] are 0.850 mol and molarity of [tex]NaNO_{3}[/tex] solution is 0.5 M. Hence, its volume is calculated as follows.[tex]Molarity = \frac{no. of moles}{Volume (in L)}\\0.5 M = \frac{0.850 mol}{Volume}\\Volume = 1.7 L (1 L = 1000 mL)\\= 1700 mL[/tex]
Therefore, the volume for 0.850 mol of [tex]NaNO_{3}[/tex] from a [tex]NaNO_{3}[/tex] solution is 1700 mL.
As given mass of LiOH are 30.0 g from a 2.70 M LiOH (molar mass = 23.95 g/mol) solution. Hence, its number of moles are calculated as follows.[tex]No. of moles = \frac{mass}{molar mass}\\= \frac{30.0 g}{23.95 g/mol}\\= 1.25 mol[/tex]
So, volume for LiOH solution is calculated as follows.
[tex]Molarity = \frac{no. of moles}{Volume (in L)}\\2.70 M = \frac{1.25}{Volume}\\Volume = 0.464 L (1 L = 1000 mL)\\= 464 mL[/tex]
Therefore, volume of 30.0 g of LiOH from a 2.70 M LiOH solution is 464 mL.
Based on the molar masses. how can you tell that an equation is balanced
What was the independent variable in Mendel's pea plant experiment?
A.The temperature
B.Cross-pollination
C.Type of plant
D.Characteristic of the offspring
4. Calculate the final temperature of 75.4 g water originally at 12.6 °C after it absorbs 3.85 kcal
of heat.
Answer:
63.7 °C
Explanation:
Step 1: Given and required data
Mass of water (m): 75.4 gInitial temperature (T₁): 12.6 °CAbsorbed heat (Q): 3.85 kcalSpecific heat capacity of water (c): 1 cal/g.°CStep 2: Calculate the final temperature of the water (T₂)
We will use the following expression.
Q = c × m × (T₂ - T₁)
T₂ = Q/c × m + T₁
T₂ = 3.85 × 10³ cal/(1 cal/g.°C) × 75.4 g + 12.6 °C = 63.7 °C
Calculate the mass of 0.900 mol of lithium thiocyanate.
Answer:
58.6 g.
Explanation:
Hello there!
In this case, since the molecular formula of lithium thiocyanate is LiCNS and therefore its molar mass is 65.1 g/mol, it possible to perform the calculation of the mass of 0.900 moles of this substance by recalling the following equivalence statement:
1 mol = 65.1 g.
Thereby, we can calculate the required mass as shown below:
[tex]0.900mol*\frac{ 65.1g}{1mol}\\\\58.6 g[/tex]
Best regards!
It takes 53.0 J to raise the temperature of an 11.0 g piece of unknown metal from 13.0∘C to 24.3 ∘C. What is the specific heat for the metal?
Answer:
51 = ( 8.2/1000)Kg ×S (11.5)
51×1000= 8.2 (11.5)S
S = 51000/94.3
S = 540.8 J/kg K
Explanation:
What is the name for Al(O)2?
Answer:
Aluminium oxide ________
What is the most likely meaning of concentration in paragraph 7?thinking thinking about about one one thing thing in in a a focused focused waywayamount amount of of a a substance substance found found in in waterwaterarea area where where something something comes comes fromfromchance chance to to be be foundfound
Answer:
amount of a substance found in water.
Answer:
amount of a substance found in water.
Explanation:
Help me please jus tell me 1 2 3 etc for the answers thank you!
Answer:
1. lakes and rivers 2. groundwater 3. watershed 4. pollution
Explanation:
What is the oxidation number of iron in FeO?
Answer:
+2
Explanation:
Answer:
2 electrons
Explanation:
In Iron (II) oxide, or Ferrous Oxide, or FeO, the Iron element (Fe) is bonded to the Oxygen, in the oxidation state of "2". This means that the Iron has accepted 2 electrons from the Oxygen.
