Answer:
Thymus. This gland makes white blood cells called T-lymphocytes that fight infection and are crucial as a child's immune system develops
Need help on science ASAP
Answer:
3
Explanation:
The plates are moving away from each other
PLEASE HELP I'M SO DOOMED
A balloon that contains 2.8 mol of helium gas has a volume of 31 L. If 3.5 g of helium is added, what will be the new volume of the balloon? Assume the temperature and pressure remain the same. The molar mass of helium is 4.00 g/mol.
a) 186 L
b) 70 L
c) 24 L
d) 41 L
Do not post links
Answer:
D
Explanation:
31 / 2.8 = 11.0714286 L per mole of helium
3.5 / 4 = 0.875 moles
2.8 + 0.875 = 3.675 moles
11.0714286 x 3.675 = 40.6875 L
6 a What does the sacrificial protection of iron mean?
b Both magnesium and zinc can be used for it. Why?
c But copper will not work. Explain why.
Explanation:
A-Corrosion
B- Magnesium helps ur body regulates its zinc levels and zinc absorbs into absorbs magnesium more efficiently
One mole of CO2(g) is expanding isothermally and reversibly from a volume of 0.100 dm3 to a volume of 100 dm3. Calculate the work in "kJ" of the expansion process if: 1/ the gas is considered real gas. (Hint: use the Van Der Waals equation for real gases to express the pressure in the work equation). 2/ The gas is considered perfect gas. Given: The constants for CO2(g) are: a= 3.59 atm L2/mol2, b= 0.0427 L/mol Answer: a) the expansion work for CO2 as real gas is W = kJ. b) the expansion work for CO2 as perfect gas is W = kJ.
Solution :
For the real gas following Vander Waals equation, reversible isothermal work done is given by :
[tex]$W= \int P \ dV$[/tex]
[tex]$W= \int \left(\frac{nR}{V-nb}-\frac{an^2}{V^2}\right) dV$[/tex]
[tex]$W_{real}=-nRT \ln \left[\frac{V_2-b}{V_1-b}\right]-an^2\left[\frac{1}{V_2}-\frac{1}{V_1}\right]$[/tex]
Given : [tex]$V_1=0.1 \ dm^3$[/tex], [tex]$$V_2 =100 \ dm^3[/tex]
[tex]$a=359 \ atm \ L^2/ mol^2, \ \ b = 0.0427 \ L/mol$[/tex]
As T is not given, assuming T = 290 K
[tex]$W_{real} = 0.0823 \times 240 \left[ \ln \left(\frac{100-0.042}{0.1-0.0427}\right)\right]-3.59\left[\frac{1}{100}-\frac{1}{0.1}\right]$[/tex]
[tex]$W_{real}= -183.06+35.864$[/tex]
[tex]$W_{real}=-147.196$[/tex]
For the perfect gas,
[tex]$W=nRT \ln\left[\frac{V_2}{V_1}\right] =(1)(0.0823)(290) \ln \left[\frac{100}{0.1}\right]$[/tex]
[tex]$W_{ideal}=169.415$[/tex] kJ
Which adaptation allowed gymnosperms and angiosperms to become the most dominant types of plants on earth?
O pollen
O flowers
O seeds
O fruit
help pleaseeee. over dilutions in chemistry
Answer:
5 L
Explanation:
We'll begin by calculating the molarity of the CaCl₂ solution. This can be obtained as follow:
Mole of CaCl₂ = 0.5 mole
Volume = 2 L
Molarity =?
Molarity = mole /Volume
Molarity = 0.5 / 2
Molarity = 0.25 M
Finally, we shall determine the volume of the diluted solution. This can be obtained as follow:
Molarity of stock solution (M₁) = 0.25 M
Volume of stock solution (V₁) = 2 L
Molarity of diluted solution (M₂) = 0.1 M
Volume of diluted solution (V₂) =?
M₁V₁ = M₂V₂
0.25 × 2 = 0.1 × V₂
0.5 = 0.1 × V₂
Divide both side by 0.1
V₂ = 0.5 / 0.1
V₂ = 5 L
Thus the volume of the diluted solution is 5 L
1. How many moles are in 3.50 grams of NaCl?
0.0600 mol
O 203 mol
O 78.4 mol
O 0.156 mol
can silver nitrate test the purity of water
How many atoms are in 9.44 moles of Al?
Answer:
c) %5.68×10²⁴
Explanation:
Number atoms=Avogadro's number ₓ number of moles
N= 6.023ₓ 10²³×9.44
N=5.68×10²⁴
What is the mass in grams of the following measurements? 1.00 mol Al ___________ 6.02 x 10 23atoms Al ___________
Answer:
Mass of 1 mole of Aluminium = Mass of 6.02 x 10 23atoms of Aluminium = 26.98 grams.
Explanation:
1 mole of any element or molecule has 6.02 x 10 23atoms or subparts.
Hence 1 mole of aluminum will also have 6.02 x 10 23atoms. Hence, it is clear that mass of 1 mole of Aluminium will be equal to 6.02 x 10 23atoms of Aluminium.
Thus,
Mass of 1 mole of Aluminium = Mass of 6.02 x 10 23atoms of Aluminium = 26.98 grams.
The substances below are listed by increasing specific heat capacity value. Starting at 30.0 °C, they each absorb 100 kJ of thermal energy. Which one do you expect to increase in temperature the most? (3 points)
a
Silver, 0.239 J/(g °C)
b
Aluminum, 0.921 J/(g °C)
c
Lithium, 3.56 J/(g °C)
d
Water, 4.184 J/(g °C)
Answer:
the answer is B
Explanation:
does anyone know this please?
Answer:
1.) b
2.) c
3.) e
4.) g
5.) j
6.) k
HOPE THIS HELPS
-Todo <3
Explanation:
Answer:B, C, F, G, I, L.
Explanation: i think that these are the correct one there was not a whole lot of contects on the question
H IT H-C --H + Ħ Н The model above shows the structural formula for ethane. What is the chemical formula for ethane? OA. C2H6 OB. 2CH3 Oc. 8CH OD. C6H2
Answer:
B
Explanation:
The driest desert on Earth is the several years to not receive any rainfall. desert. There it has been recorded for O Atacama Sahara (T) Antartic ( Gobi
Answer:
Atacama
Explanation:
Can someone answer this, NO ROBOTS!!!!
Genetic engineering improved the lives if individuals with insulin because it helps the body use and store sugar, since people with diabetes can't produce insulin.
omg pls help i dunno what the frick frack this is
Answer:
1. Mass of KCl produced = 774.8 g of KCl
2. Mass of KNO₃ produced = 13.837g
3. Moles of NaOH made = 0.846 moles
4. Moles of LiCl produced = 0.846 moles
5. Moles of CO₂ produced = 207.6 moles
Explanation:
1. From the equation of reaction, 1 mole of ZnCl₂ produces, 2 moles of KCl.
5.02 moles of ZnCl₂ will produce, 2 × 5.02 moles of KCl = 10.4 moles of KCl
Molar mass of KCl = (39 + 35.5) g/mol = 74.5 g/mol
10.4 moles of KCl = 10.4 × 74.5 g
Mass of KCl produced = 774.8 g of KCl
2. Mole ratio of KNO₃ and KOH = 1:1
O.137 moles of KOH will produce 0.137 moles of KNO₃
Molar mass of KNO₃ = 101 g/mol
Mass of KNO₃ produced = 0.137 × 101 g = 13.837g
3. Molar mas of Ca(OH)₂ = 74.0 g
Moles of Ca(OH)₂ in 31.3 g = 31.3/74.0 = 0.423 moles of Ca(OH)₂
Mole ratio of NaOH and Ca(OH)₂ in the reaction = 2 : 1
Moles of NaOH made = 2 × 0.423 = 0.846 moles
4. Molar mass of MgCl₂ = 95.0 g
Moles of MgCl₂ in 40.2 g = 40.2/95.0 = 0.423 moles
From the reaction equation, mole ratio of MgCl₂ and LiCl = 1:2
Moles of LiCl produced = 2 × 0.423 = 0.846 moles
5. From the equation of reaction, 1 mole of C₆H₁₀O₅ produces 6 moles of cO₂
34.6 moles of C₆H₁₀O₅ will produce 34.6 × 6 moles of CO₂
Moles of CO₂ produced = 207.6 moles
The air we breathe is a(n) _____.
Q3. When copper (II) chloride reacts with silvernitrate, copper (II) nitrate and silverchloride are formed.Write the balanced equation for the reaction given above:A.CuCl2(aq) + 2 AgNO3(aq) →Cu (NO3)2(aq) + 2 AgCl(s)B.CuCl2(aq) + NaNO3(aq) →Cu (NO3)2(aq) + AgCl(s)C.CuCl2(aq) + 2 NaNO2(aq) →Cu (NO2)2(aq) + 2 AgCl(s)D.CuCl(aq) + NaNO3(aq) →Cu NO3(aq) + AgCl(aq
Answer:
See explanation
Explanation:
When we are writing chemical reaction equations, we must ensure that such equations are balanced. That is, the number of atoms of each element on both sides of the reaction equation are exactly the same.
After we identify the formula of each compound in the reaction, then we proceed the write the balanced reaction equation as follows;
CuCl2 + 2AgNO3 -------> Cu(NO3)2 + 2AgCl
If you have 1.5 grams of silver nitrate, how many grams of silver could
you produce?
Answer:
0.95g of Ag we can produce
Explanation:
To solve this question we have to convert the mass of silver nitrate (AgNO₃) to moles. The moles of silver nitrate = Moles of Ag. Then, with molar mass of Ag we can know the mass of silver:
Moles AgNO₃ -Molar mass: 169.87g/mol-:
1.5g * (1mol / 169.87g) = 0.0088 moles Ag
Mass Ag -Molar mass: 107.87g/mol-:
0.0088 moles Ag * (107.87g / mol) =
0.95g of Ag we can produceCells in different tissues or organs (skin, eye, bone, etc.) contain different DNA. true or fasle,?
Answer:
false
Explanation:
trust
Answer:
True
Explanation:
Because they require different things and have different functions
A gas has a volume of 15.0 ml at 25 degree Celsius. What is the volume of the gas at 50 degree Celsius.
Answer:
30.0ml
Explanation:
Half of fifty is 25 and 25 represents 15.0ml so 15.0ml×2=30.0ml there for 25+25 is 50
In an effort to sanitize his water, Beethoven knows that bromine can be used to purify water. If Beethoven has 2.12 x 1022 formula units of aluminum bromide are reacted with excess chlorine gas, how many milliliters of liquid bromine (density = 3.12 g/mL) are formed?
Answer:
2.7 mL
Explanation:
The equation of the reaction is;
2AlBr3 + 3Cl2 -----> 2AlCl3 + 3Br2
Number of moles in 2.12 x 1022 formula units of aluminum bromide
1 mole of AlBr3 = 6.02 * 10^23 formula units
x moles = 2.12 x 1022 formula units
x = 2.12 x 1022 formula units * 1 mole/ 6.02 * 10^23 formula units
x = 0.0352 moles of AlBr3
According to the reaction equation;
2 moles of AlBr3 produces 3 moles of Br2
0.0352 moles of AlBr3 produces 0.0352 moles * 3 moles /2 moles
= 0.0528 moles of Br2
Mass of Br2 produced = 0.0528 moles of Br2 * 159.808 g/mol
Mass of Br2 produced = 8.44g
But density = mass/volume
volume = mass/density
volume of Br2 = 8.44 g/ 3.12 g/mL
volume of Br2 = 2.7 mL
2. Suppose two astronauts were outside of the space shuttle orbiter while orbiting Earth. The audio speaker in the helmet of one of the astronauts quits working. The other astronaut is only one meter away, so she shouts a message to him. Can he hear her? Explain.
Type the correct answer in the box. Express your answer to two significant figures.
A reaction between 1.7 moles of zinc Ipdide and excess sodium carbonate ylelds 12.6 grams of zinc carbonate. This is the equation for the
reaction:
Na2CO3 + Zniz - 2Nal +
ZnCoz.
What is the percent yield of zinc carbonate?
The percent yield of zinc carbonate is
5.91
1X.
Answer: The percent yield of zinc carbonate is 5.91 %
Explanation:
To calculate the moles :
[tex]\text{Moles of solute}=\frac{\text{given mass}}{\text{Molar Mass}}[/tex]
[tex]\text{Moles of} ZnCO_3=\frac{12.6 g}{125.4g/mol}=0.100moles[/tex]
[tex]ZnI_2[/tex] is the limiting reagent as it limits the formation of product and [tex]Na_2CO_3[/tex] is the excess reagent.
[tex]Na_2CO_3+ZnI_2\rightarrow 2NaI+ZnCO_3[/tex]
According to stoichiometry :
1 mole of produce = 1 mole of
Thus 1.7 moles of [tex]ZnI_2[/tex] will produce=[tex]\frac{1}{1}\times 1.7=1.7moles[/tex] of [tex]ZnCO_3[/tex]
Theoretical yield of [tex]ZnCO_3=moles\times {\text {Molar mass}}=1.7moles\times 125.4g/mol=213.2g[/tex]
percentage yield = [tex]\frac{\text {Experimental yield}}{\text {Theoretical yield}}\times 100=\frac{12.6g}{213.2g}\times 100=5.91\%[/tex]
Answer:
the other person was right EXCEPT it says in 2 significant numbers so the answer is 5.9
Explanation:
i hope this helps. have a wonderful day :))
A sample of oxygen gas occupies a volume of 250 mL at .8 atm of pressure. What volume will it occupy at 1.2 atm of pressure?
Metallic bonding is sometimes referred to as a "sea of electrons." I sometimes picture is as cheerios (nuclei) floating around in milk (valence electrons). And while metallic bonding has the name "bond" it can be very different from Ionic and Covalent Bonds.
In complete sentences describe how Metallic bonds are alike, and how they are different from the other bond types we have studied.
The products of self-ionization of water are
H+
H20
H+ and OH-
OH-
Answer:
3
H+ and OH-
Explanation:
What evidence from the experiment shows that conduction occurred? In your answer, be sure to include the materials involved in the transfer of heat through conduction.
Answer:
Sample Response: The melting of the chocolate pieces one by one showed that it was caused by heat flowing through the foil bridge. The transfer of heat happened between the foil bridge and the chocolate pieces because they were touching each other.
Answer:
The conduction was made by the foil which was touching the chocolate made the chocolate slowly melt because of the tea light giving heat to the foil the foil conducted it to the chocolate causing it to melt.
Explanation:
Conduction is the transfer of heat through touch.
Convection is the transfer of heat through liquid or gas.
Radiation is how heat/energy travels through space.
Hope this helped!
Four metals were kept in contact with each other. The table below shows the initial temperature of the metals.
Metal Initial Temperature
А
30 °C
B
42 °C
С
25 °C
D
16°C
From which metal will heat flow into all the other metals?
Metal A
Metal B
Metal C
Metal D
Answer:
The answer is B
Explanation:
I'm just big-brained
And because it's hotter than the rest and since all of them are cold "B" is just going to make them warmer.
Which statement regarding this equation is TRUE?
4Fe (s) + 3O2 (g) —> 2Fe2O3 (s)
There are 2 reactants.
The coefficient on O2 is 8.
Iron (III) oxide is a gas.
There are 5 atoms of oxygen on the reactant side.
Answer:
iron (III) oxide is a gas