Answer:
s orbital
Explanation:
it has the lowest energy because
Paulis law state that orbitals with lower energy must be fill first before that of higher energy
and the s orbital is filled first
1125 J of energy is used to heat 250 g of iron to 55 °C. The specific heat capacity of iron is 0.45 J/(g·°C).
What was the temperature of the iron before it was heated?
55 °C
55 °C
35 °C
35 °C
45 °C
45 °C
20 °C
Answer:
45 °C.
Explanation:
From the question given above, the following data were obtained:
Heat (Q) = 1125 J
Mass (M) = 250 g
Final temperature (T₂) = 55 °C
Specific heat capacity (C) = 0.45 J/gºC
Initial temperature (T₁) =?
The initial temperature of the iron can be obtained as illustrated below:
Q = MC(T₂ – T₁)
1125 = 250 × 0.45 (55 – T₁)
1125 = 112.5 (55 – T₁)
Divide both side by 112.5
1125/112.5 = 55 – T₁
10 = 55 – T₁
Collect like terms
10 – 55 = –T₁
–45 = –T₁
Multiply through by –1
45 = T₁
T₁ = 45 °C
Therefore, the initial temperature of the iron is 45 °C
What is the pressure of 4 moles of helium in a 50 L tank at 308 K?
Use PV = nRT.
A. 24.64 atm
B. 0.13 atm
O C. 0.51 atm
D. 2.02 atm
Answer:
D
Explanation:
P = Pressure
V = Volume
n = Moles
R = .08206 (because we're using liters)
T = Temperature (as K)
P(50) = (4)(.08206)(308)
P(50) = 101.09792
Divide both sides by 50
P(50)/50 = 101.09792/50
P = 2.0219584
Answer:
[tex]\boxed {\boxed {\sf D. \ 2.02 \ atm}}[/tex]
Explanation:
We are asked to find the pressure of helium gas using the ideal gas law.
[tex]PV= nRT[/tex]
In this formula P is the pressure, V is the volume, n is the number of moles of gas, R is the universal gas constant, and T is the temperature.
The pressure is unknown and we are solving for it. The volume is 50 liters, there are 4 moles of helium gas, the universal gas constant is 0.08206 L *atm/ mol * K, and the temperature is 308 Kelvin.
[tex]\bullet \ V= 50 \ L \\\bullet \ n= 4 \ mol \\\bullet \ R = \frac {0.08206 \ L * atm}{mol *K}\\\bullet \ T= 308 \ K[/tex]
Substitute these values into the formula.
[tex]P * 50 \ L= 4 \ mol * \frac {0.08206 \ L * atm}{mol *K} * 308 \ K[/tex]
Multiply on the right side. The units of moles (mol) and Kelvin (K) cancel each other out.
[tex]P* 50 \ L = 4 * 0.08206 \ L *atm * 308[/tex]
[tex]P*50 \ L =0.32824 \ L * atm *308[/tex]
[tex]P* 50 \ L = 101.09792 \ L * atm[/tex]
We are solving for the pressure, so we must isolate the variable P. It is being multiplied by 50 liters. The inverse operation of multiplication is division, so divide both sides by 50 L.
[tex]\frac {P* 50 \ L}{50 \ L} = \frac {101.09792 \ L * atm}{50 \ L}[/tex]
[tex]P= \frac {101.09792 \ L * atm}{50 \ L}[/tex]
The units of liters (L) cancel.
[tex]P= \frac{101.09792}{50 } \ atm[/tex]
[tex]P= 2.0219584 \ atm[/tex]
If we round to the nearest hundredth place the 1 in the thousandth place tells us to leave the 2 in the hundredth place.
[tex]P \approx 2.02 \ atm[/tex]
The pressure is approximately 2.02 atmospheres and choice D is correct.
The unit of force newton is a derived unit.Why?
Answer:
Why is the unit of force called a derived unit? That's because the Newton is defined in terms of other units which are more fundamental. One Newton is the force required to accelerate a mass of one kilogramme at the rate of one metre per second squared.
WILL MARK BRAINLY IF GOOD ANSWER :)
Chlorine and oxygen are both gases at room temperature. What are some characteristic properties of chlorine that distinguish it from oxygen?
Answer:
Well one characteristic is electical energy transforms into thermal energy and gases and the state of matter(one of the distinct form i which matter exist)
solution is an example of______mixtures
Answer:
homogeneous mixture must be the answer
A fixed mass of gas has a volume of 92 cm cube and 3 degrees Celsius. What will be its volume at 18 degrees celsius if the pressure remains constant?
Answer:
94.8454
Explanation:
Let volume be V
Let Temperature be T
V1= 92
T1= 3C but to kelvin 273+3= 300K
V2= ?
T2= 18 C but to kelvin 18+273= 291
[tex] \frac{v1}{t1} = \frac{v2}{t2} [/tex]
[tex] \frac{92}{300} = \frac{v2}{291} [/tex]
[tex]v2 \times 300 = 92 \times 291[/tex]
[tex]v2 = \frac{92 \times 291}{300} [/tex]
[tex]v2 = 94.8454[/tex]
Question 2: thanks!!!
Oxit bazơ có những tính chất hóa học nào?
Answer:
tác dụng với acid,
Explanation:
Identify any three acids.
Identify any three bases.
PLEASE HELP URGENT!!
What is the SI system? What are its benefits?
Answer:
The SI system : The international system of units.
It is a scientific method of expressing the magnitudes or quantities of important natural phenomena.
Benefits of SI system
It is a coherent system of units ( a system based on certain sets of fundamental units )It is a rational system of units ( it assigns only one unit to a particular physical quantity )what is the balanced equation of 2HCl + Mg - MgCla + Ha
2HCl + Mg => MgCl2 + H2
Which reaction occurs at the cathode in an electrochemical cell?
A. Cu(s) → Cu2+(aq) + 2e
B. Cu2+(aq) + H2(g) → Cu(s) + 2H+(aq)
C. Cu(s) + 2H+(aq) → Cu2+(aq) + H2(g)
D. Cu2+(aq) + 2e → Cu(s)
Answer:
I could be wrong but I say it's letter b
Explanation:
I hope you have an great night
Which of the following is the formula for vanadium (II) oxide? Question 11 options: A) VO2 B) VO C) V2O3 D) V2O5
Answer: A. ( VO2)
Explanation:
Answer:
B) VO
Vanadium(II) oxide is the inorganic compound with the idealized formula VO.
In a hospital, bags of saline solution are used to rehydrate patients. They are made by dissolving a specific amount of salt in water. What is the solvent in the saline solution?
A. Bag
B. Patient
C. Saline
D. Water
Water is the solvent in the saline solution. Hence, option D is correct.
What is the solute?A solute is something being dissolved, a solvent is a thing dissolving the item, and the solution is the mixture of the two items.
In a hospital, bags of saline solution are used to rehydrate patients. They are made by dissolving a specific amount of salt in water. Water is the solvent in the saline solution.
Hence, option D is correct.
Learn more about the solution here:
https://brainly.com/question/7932885
#SPJ5
PLZ HELP ME Which of the following is the process by which chloroplasts use carbon dioxide, water, and sunlight to produce sugars and oxygen?
A. Photosynthesis
B. Cellular respiration
c. Reproduction
D. Homeostasis
Answer:
a
Explanation:
one similarity between physics and chemistry is...
Answer:
They are branch of science.
Explanation:
hope this helps
Answer:
Branch's of science yk
Explanation:
I'm smart lol
Which of the following is an example of a chemical change?
A. Sugar breaking down into water and carbon when it is heated
B. A sugar cube being crushed by a spoon
C. Sugar mixing with red food coloring and forming a red solid
D. A sugar cube dissolving in water as the water is stirred
Answer:
I think its sugar breaking down into watee and carbon when it is heated
I HOPE ITS RIGHT IF NOT THEN SORRYHAVE A GREAT DAY :)
2 Figure 3.1 shows two different forms of carbon, A and B.
A
B
Figure 3.1
a Name the two forms of carbon shown.
Answer:
show the pictures pls specify
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
Explain which intermolecular force is primarily responsible for the unusually high boiling point of H2OH2O. Compare the strengths of intermolecular forces of attraction present in a sample of liquid water to the strengths of intermolecular forces of attraction present in liquid samples of H2SH2S, H2SeH2Se, and H2TeH2Te. Justify your answer using the information presented in both tables, and complete the statements below.
Answer:
See explanation
Explanation:
Intermolecular forces are forces of attraction that exist between molecules of a substance in a particular state of matter.
The dominant intermolecular force of attraction in H2O is the hydrogen bond. The hydrogen bond exists between molecules of a substance when the substance is made of hydrogen atoms bonded to atoms of a highly electronegative element. Hence, strong hydrogen bonding accounts for the high boiling point of water.
The magnitude of hydrogen bonding between molecules depends on the electro negativity of the atoms to which hydrogen is bonded.
The more the electro negativity of the atoms to which hydrogen is bonded, the greater the magnitude of intermolecular hydrogen bonding.
Since the electro negativity of elements decrease down the group, the strength of intermolecular hydrogen bonding between the molecules decreases as follows;
H2O> H2S> H2Se> H2Te
aluminum hydroxide molecular weight step by ste
Balance in basic solution: O2(g) + Cr³+ (aq) → H₂O2 (1) + Cr₂O7²- (aq)
cr2o72+H2o2-(r3+o2)
Explanation:
r62o72+H2o2-(r3+o2)
calcium hydrogen sulphite cress cross
Answer:
Ca Hso4 ×
Explanation:
Because i did whT you said
Infrared waves are an example of heat transfer by
A. convection
B. radiation
C. conduction
D. motion of the air
Answer:
convection is my correct answer
How much heat is added if .0948g of water is increased in temperature by .728 degrees C?
.289 J
.803 J
1.46 J
.055 J
Answer:
0.289J of heat are added
Explanation:
We can relate the change in heat of a substance with its increasing in temperature using the equation:
q = m*ΔT*S
Where Q is change in heat
m is mass of substance (In this case, 0.0948g of water)
ΔT = 0.728°C
S is specific heat (For water, 4.184J/g°C)
Replacing:
q = 0.0948g*0.728°C*4.184J/g°C
q = 0.289J of heat are added
Which of the following materials contains a base?
a. Stomach digestive juices
b. Orange juice
c. Ammonia window cleaner
d. Vinegar
Answer:
c. ammonia window cleaner
Explanation:
Window cleaners contain ammonia (a base) for the purpose of removing the dust and grease on the windows.
digestive juices, orange(a citrus) juice, and vinegar are all highly acidic.
... give me brainliest please :)) ...
Doing my summer school work right now. Please help me pass I don’t want to take chemistry for the third time.
Answer:
13.B 0.15 M KBr
14.C 1 M C²h⁵OH
15.D 0.1 M C⁶H¹²o⁶
16.A 2 K² SO⁴
17.A 2 M K² SO⁴
18.D 0.028 M KBr
19.A 1 M Nal
20.B 0.1 M AICI³
calculate the maximum mass of ethanol that could be obtained from 30.0g of glucose
Answer:
15.3g
Explanation:
C6H12O6 → 2C2H5OH + 2CO2
1 mol C6H12O6 = 180g
1 mol CH3-CH2-OH = 46g
From 180g glucose ethanol can get = 92g
30g glucose ethanol gives us = (92*30)/180 = 15.33g
what is the most appropriate unit to measure the following; the length of a football field. b) the diameter of a tennis ball
Explanation:
a) m (metre)
b) mm (millimeter)
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:
https://brainly.com/question/13440548
#SPJ2
