Answer:
its 2
Explanation:
Will give brainliest
(1) Phosphorus silicon is a semi-conductor
When Silicone is altered with Phosphorus, 4 of its electrons form covalent bonding and the 5th electron becomes delocalized and thus it increases electrical conduction
Answer:
blue blah blue blah
Explanation:
Which word describes the amount of matter an object contains?
altitude
density
mass
pressure
Answer:
Mass
Explanation:
Answered this question multiple times and got it correct
Hope this helped!
Stay safe!
Atoms are stationary and don't move when in solid form.
False
True
Answer:
True? The don't stay exactly still i dont think, but i'd say true.
Explanation:
Answer:
TRUE
Explanation:
In a solid, atoms are packed tightly together and move very slowly. In fact, they do not flow at all: they simply vibrate back and forth.
Key words vibrate, not movement.
Correct me if I'm wrong of course
A 275 g sample of a metal requires 10.75 kJ to change its temperature from 21.2 oC to its melting temperature, 327.5 oC. What is the specific heat of this metal
Answer:
[tex]c=0.127\ J/g^{\circ} C[/tex]
Explanation:
Given that,
Mass of the sample, m = 275 g
It required 10.75 kJ of heat to change its temperature from 21.2 °C to its melting temperature, 327.5 °C.
We need to find the specific heat of the metal. The heat required by a metal sample is given by :
[tex]Q=mc\Delta T[/tex]
c is specific heat of the metal
[tex]c=\dfrac{Q}{m\Delta T}\\\\c=\dfrac{10.75\times 10^3\ J}{275\times (327.5 -21.2)}\\\\=0.127\ J/g^{\circ} C[/tex]
So, the specific heat of metal is [tex]0.127\ J/g^{\circ} C[/tex].
(5) Use scientific notation, make the following conversions:
6.20 km to m
Answer:
6200 meters
Explanation:
To convert from km to m you have to multiply the number by a thousand
Answer:
6.2×10^3 m
Explanation:
6.20×1000=6200m
In scientific notation 6200 = 6.2×10^3
How many milliliters of 60% carbonic acid must be mixed with how many milliliters of 15% carbonic acid to make 650 milliliters of a 38% carbonic acid solution
Answer:
348.9 mL of the 60% solution and 251.1 mL of the 15% solution.
Explanation:
First, we calculate how many mililiters of pure carbonic acid are there in 650 mL of a 38% solution:
650 mL * 38/100 = 247 mLThen we can express the sum of both initial solutions as:
1) x * 60/100 + y * 15/100 = 247for the volume of carbonic acid; and
2) x + y = 600 mLFor the volume of the solutions.
We now have a system of two equations and two unknowns (x is the volume of the 60% solution and y is the volume of the 15% solution).
We express x in terms of y in equation 2):
x = 600 - yAnd replace x in equation 1):
(600 - y) * 60/100 + y * 15/100 = 247360 - 0.6y + 0.15y = 247-0.45y = -113y = 251. 1 mLFinally we calculate x using equation 2):
x + 251.1 = 600x = 348.9 mLWhat is the molecular formula for a compound with a molar mass of 42.08g/mol and an empirical formula of ch2
Answer:
[tex]C_3H_6[/tex]
Explanation:
Hello!
In this case, since the empirical formula is the smallest representation of the molecular formula, it is known that the times in which the empirical formula is into the molecular formula is a whole number and is computed by dividing the molar mass of the molecular formula by that of the empirical formula as shown below:
[tex]\frac{42.08g/mol}{12.01+1.01x2}= \frac{42.08g/mol}{14.03g/mol}=3[/tex]
Thus, the molecular formula times the empirical formula by 3 to obtain:
[tex]C_3H_6[/tex]
Regards!
What is the wavelength of light emitted when the electron in a hydrogen atom undergoes transition from an energy level with n = 4 to an energy level with n = 2?
Answer:
[tex]4.86\times10^{-7}\ \text{m}[/tex]
Explanation:
R = Rydberg constant = [tex]1.09677583\times 10^7\ \text{m}^{-1}[/tex]
[tex]n_1[/tex] = Principal quantum number of an energy level = 2
[tex]n_2[/tex] = Principal quantum number of an energy level for the atomic electron transition = 4
Wavelength is given by the Rydberg formula
[tex]\lambda^{-1}=R\left(\dfrac{1}{n_1^2}-\dfrac{1}{n_2^2}\right)\\\Rightarrow \lambda^{-1}=1.09677583\times 10^7\left(\dfrac{1}{2^2}-\dfrac{1}{4^2}\right)\\\Rightarrow \lambda=\left(1.09677583\times 10^7\left(\dfrac{1}{2^2}-\dfrac{1}{4^2}\right)\right)^{-1}\\\Rightarrow \lambda=4.86\times10^{-7}\ \text{m}[/tex]
The wavelength of the light emitted is [tex]4.86\times10^{-7}\ \text{m}[/tex].
How would a long period without sunlight affect the food web?
It would cause consumers to consume more food.
It would have no effect on the food web.
It would stop decomposers from breaking down matter.
It would stop producers from producing food.
Answer: it would stop producers from producing food.
Explanation: why? Without the action of the producers to turn sunlight into food, the producers would die, and consumers that rely on them would lose their food source and die too.
Answer:
It would stop producers from producing food
Explanation:
Producers would die, and if producers died, consumers would die too.
Hope this helps
A 2.26 M solution of KOH is prepared. Calculate the moles and mass of solute present in a 15.2-mL sample of this solution. The molar mass of KOH is 56.11 g/mol.
Answer:
0.0344 moles and 1.93g.
Explanation:
Molarity is defined as the ratio between moles of a solute (In this case, KOH), and the volume. With molarity and volume we can solve the moles of solute. With moles of solute we can find mass of the solute as follows:
Moles KOH:
15.2mL = 0.0152L * (2.26mol / L) = 0.0344moles
Mass KOH:
0.0344 moles * (56.11g/mol) = 1.93g of KOH
CHEMISTRY HELP
Once the following equation is balanced, what is the correct coefficient for Z₂?
Answer:
The coefficient of Z₂ is 1.
Explanation:
From the question given above:
X + ZY —> XY + Z₂
Next, we shall balance the equation to obtain the coefficient of Z₂. This can be obtained as follow:
X + ZY —> XY + Z₂
There is 1 atom of Z on the left side and 2 atoms on the right side. It can be balance by putting 2 in front of ZY as shown below:
X + 2ZY —> XY + Z₂
There are 2 atoms of Y on the left side and 1 atom on the right side. It can be balance by putting 2 in front of XY as shown below:
X + 2ZY —> 2XY + Z₂
Now, we have 1 atom of X on the left side and 2 atoms on the right side. It can be balance by putting 2 in front of X as shown below:
2X + 2ZY —> 2XY + Z₂
Now the equation is balanced.
Thus, the coefficient of Z₂ is 1.
Give the IUPAC name for each compound.
Answer:
a. 1-fluoro-3,3,4-trimethyl-pentane.
b. 1-iodo-3-ethyl-2-methyl-hexane.
c. 1,3-dichloro-5-dimethyl-hexane.
d. 1-bromo-3-methyl-cyclopentane.
Explanation:
Hello!
In this case, according to the IUPAC rules for the listed alkyl halides, we first need to name the halogens (considering periodic order) then alkyl radicals and finally the parent chain; thus, the names are given below:
a. 1-fluoro-3,3,4-trimethyl-pentane.
b. 1-iodo-3-ethyl-2-methyl-hexane.
c. 1,3-dichloro-5-dimethyl-hexane.
d. 1-bromo-3-methyl-cyclopentane.
e. 5-chloro-1-bromo-1,1,5-trimethyl-pentane (radicals are not clear).
Best regards!
What are 3 characteristics of all invertebrates
Answer:
None have backbones
No cell walls
Multicellular
Includes radial or bilateral body symmetry.
Explanation:
Which two statements are true about all generators?
They convert motion energy to electric energy.
They have a fixed pair of magnets and a rotating metal coil.
They’re powered by fossil fuels.
They convert electric energy to motion energy.
They use the relative motion of a magnet and a coil of wire.
Answer:
they have a fixed pair of magnets and a rolling coil they convert motion into electric energy they are powered by fosile fuels they use reletive motion of a magnet and coil of a wire
Explanation:
Answer:
They convert motion energy to electric energy.
They use the relative motion of a magnet and a coil of wire.
Explanation:
This is the correct answer.
What is a molecule contains the genetic instructions for the development and functioning of all living organisms found in the nucleus of a cell
What carpet Burns in a deficiency of O2 a mixture of CO and CO2 forms.Carbon Burns in excess O2 to form only CO2 and CO Burns in excess O2 to form only CO2. Calculate ΔH for C(graphite +1/2O2) →CO(g).
Answer:
Explanation:
From the combustion of carbon, the reactions occurring in limited oxygen conditions are:
[tex]C(graphite) + \dfrac{1}{2}O_{2(g)} \to CO_{(g)}[/tex]
[tex]C(graphite) + O_{2(g)} \to CO_{2(g)}[/tex]
If it occurs in excess, then any leftover CO changes to CO2. i.e.
[tex]C(graphite) + O_{2(g)} \to CO_{2(g)}[/tex] ---- (1)
[tex]CO_{(g)} + \dfrac{1}{2}O_{(g)} \to CO_{2(g)}[/tex] ----- (2)
From (1), the enthalpy change is:
[tex]\Delta H_{rxn1} = \Delta H^0_{fCO_2(g)} - ( \Delta H^0_{f C(graphite)}+ \Delta H^0_{fCO_2(g)}[/tex]
[tex]\Delta H_{rxn1} =-393.5 \ kJ/mol -(0+0)[/tex]
[tex]\Delta H_{rxn1} =-393.5 \ kJ/mol[/tex]
From (2), the enthalpy change is:
[tex]\Delta_{rxn2} = \Delta H^0_{fCO_2(g)} - ( \Delta H^0_{fCO(g)} + \dfrac{1}{2} \Delta H^0_{fO_2(g)})[/tex]
[tex]\Delta_{rxn2} = -393.5 \ kJ/mol -(-110.5 + \dfrac{1}{2}(0))[/tex]
[tex]\Delta_{rxn2} = -283.0 \ kJ/mol[/tex]
Subtracting (2) from (1), we get:
[tex]C(graphite) + O_{2(g)} \to CO_{2(g)} \ \ \ \Delta H_{rxn} = -393.5 \ kJ/mol}[/tex]
[tex]CO_{(g)} + \dfrac{1}{2} O_2(g) \to CO_{2(g)}} \ \ \ \Delta H _{rxn2} = -283.0 \ kJ/mol[/tex]
[tex]C(graphite) + O_{2(g)} \to CO (g) + \dfrac{1}{2}O_{2(g)} \ \ \ \Delta H_{rxn} = -110.5 \ kJ/mol[/tex]
[tex]C(graphite) + \dfrac{1}{2} O_{2(g)} \to CO (g) \ \ \ \Delta H_{rxn} = -110.5 \ kJ/mol[/tex]
The enthalpy change ΔH of the reaction = -110.5 kJ/mol
9. Which of these is not a mixture? *
Solution
Alloy
Amalgam
They are all mixtures.
Answer:
They are all mixture
Explanation:
last option
Identify the type of solid from the description. Select from the following choices: metallic solid, network solid, molecular solid, ionic solid, or amorphous solid
Identify the type of solid from the description. Select from the following choices: metallic solid, network solid, molecular solid, ionic solid, or amorphous solid. a. This solid is ductile and conducts electricity.b. This solid is not conductive and has a low melting point.
Answer:
See explanation
Explanation:
A is a Metallic Solid
Let us look again at the physical properties of metals;
Metals are
DuctileMalleableSonorousHigh melting pointConducts electricityWe can now see that both ductility and electrical conductivity are metallic properties.
B is a Molecular solid
Molecules are formed when atoms share electrons. In molecules, there are no free electrons hence molecules do not conduct electricity.
Secondly, molecules are held together in the solid state by weak dispersion forces hence molecular solids have a low melting point.
radiation is a measure of average kinetic energy of particles in an object true or false
Answer:false
Explanation:
Give an example of chemical reaction that occurs in everyday life
Answer: metal and salt water
Explanation: salt starts to brake down metal and metal is everywhere in the ocean hope this helps
Answer:
baking a cake.
Explanation:
baking a cake is an example of a chemical reaction that happens daily because a new substance is forming when the cake is being baked. hope this helps! :)
The order is Solumedrol 3 mg/kg for a child weighing 20 kg. Solumedrol is available as 125 mg/2ml. How many ml will be given
Answer:
0.96mL must be given
Explanation:
First, we need to obtain the mass of Solumedrol required for the child by using its mass. Then, with this mass we can solve the volume that must be administered:
Mass of solumedrol required:
20kg * (3mg / kg) = 60mg of solumedrol are required.
Volume given:
60mg Solumedrol * (2mL / 125mg) =
0.96mL must be given
An isotope has three forms. 30% have a mass of 4 amu, 20% have a mass of 5 amu and
50% have a mass of 3 amu, Average atomic mass will be closest to
The average atomic mass will be 3.70 amu
We have to obtain the average atomic mass by multiplying the mass of each isotope in amu by the relative abundance of the given isotope as contained in the data of the question.
Hence;
Average atomic mass;
(0.30 * 4) + (0.20 * 5) + (0.50 * 3)
= 1.20 + 1.00 + 1.50
= 3.70 amu
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How do sound waves travel? PLEASE HELP IF YOU WANT BRAINLEIST AND ME TO LIKE URE COMMENT!!
A. Sound causes the air near it to vibrate inwards.
B. waves radiate outward from a central point.
C. Sound moves randomly in different directions.
D. Sound transforms waves into different frequencies.
The answer is A. The vibration caused by the waves through the air eventually weaken, which is why sound diminishes easily over distance.
A patient is prescribed 100mg/day of antibiotic for 2 weeks. The antibiotic is available in vials that contain 20mg/vial of the drug. How many vials are necessary for the entire treatment?
Which is the weakest type of intramolecular force/bond?
a. Polar covalent b. Ionic c. Metallic d. Nonpolar covalent
Answer:
Non polar covlant
Explanation:
which element can form an oxide with the general formula m2o or mo where m is a metal
Answer:
Because the compound has a formula of M2O, the number of valence electrons of M should be 1. Therefore, (1) Group 1 is the correct answer because elements in group 1 have 1 valence electron.
Explanation:
