Answer:
wavelength = 6 cm .
Explanation:
frequency given = 5 x 10⁹ .
wavelength = velocity of light / frequency
= 3 x 10⁸ / 5 x 10⁹
= .06 m
= 6 cm
If 1.50 L of 0.780 mol/L sodium sulfide is mixed with 1.00 L of a 3.31 mol/L lead(II) nitrate solution, what mass of precipitate would you expect to form?
Answer:
336.1 g of PbS precipitate
Explanation:
The equation of the reaction is given as;
Na2S(aq) + Pb(NO3)2(aq) ----> 2NaNO3(aq) + PbS(s)
Ionically;
Pb^2+(aq) + S^2-(aq) -----> PbS(s)
Number of moles of sodium sulphide= concentration of sodium sulphide × volume of sodium sulphide
Number of moles of sodium sulphide= 0.780 × 1.5 = 1.17 moles
Number of moles of lead II nitrate= concentration of lead II nitrate × volume of lead II nitrate
Number of moles of lead II nitrate= 3.31× 1.00= 3.31 moles
Then we determine the limiting reactant. The limiting reactant yields the least amount of product.
Since 1 moles of sodium sulphide yields 1 mole of lead II sulphide
1.17 moles of sodium sulphide also yields 1.17 moles of lead II sulphide
Hence sodium sulphide is the limiting reactant.
Thus mass of precipitate formed= amount of lead II sulphide × molar mass of sodium sulphide
Molar mass of lead II sulphide= 287.26 g/mol
Mass of lead II sulphide = 1.17 moles × 287.26 g/mol
Mass of lead II sulphide= 336.1 g of PbS precipitate
If the temperature outside increases, but the amount of water vapor stays the same, what happens to the relative humidity? (50 points, please explain)
If the water vapor content remains the same and the temperature decreases, the relative humidity rises.
If the water vapor content remains the same and the temperature increases, the relative humidity falls.
This is because colder air doesn’t need as much moisture to become saturated as warmer air.
Hope this helps
Describe one way in which uranium is disposed of.
Answer:
In the oxide form, uranium can be disposed of as low-level radioactive waste at an approved disposal facility. Approximately 350,000 tons of anhydrous HF are used annually in the United States.
Explanation:
Predict your observation if a magnesium ribbon is put in potassium hydroxide solution and tested with a lighted wooden splinter.
mg reacts with the acid and produce visible bubbles of hydrogen gas. they will produce audible pops as the hydrogen ignites. ... Hydrochloric acid is a corrosive liquid. Hydrogen gas is explosive.
How marly electrons are in an atom of elemental
sodium?
Answer: 11 Electrons
Explanation:
We know that the atomic number of sodium is 11. This tells us that sodium has 11 protons and because it is neutral it has 11 electrons.
Answer:
The sodium atom is left with a full outermost electron shell with eight electrons, and the outermost shell of the other atom is full as well.
Explanation:
The sodium atom now has a positive electrical charge of plus 1, and the other atom has a negative charge of minus 1. The two opposite charges attract, and the two atoms now form the molecule of a compound.
What shape would a molecule with two bound groups and two lone pairs
have?
A. Trigonal pyramidal
B. Tetrahedral
C. Linear
D. Bent
Answer:
It would have to be D, a bent shape
Explanation:
I just took the quiz
4. Why does ammonia, NH3, behave as a base when it reacts with an acid?
A It accepts a neutron and becomes NH3+.
B It accepts a proton and becomes NH4+.
OC It donates a proton and becomes NH2
B is the answer ,ammonium accepts a proton and becomes ammonium ion
What is sodium bicarbonate an example of? a buffer an acid a liquid a base
Answer:
base
Explanation:
carbonic acid - H2CO3 - is a weak acid. Therefore, HCO3 itself is its conjugate base. The Na(sodium) ion is neutral.
This means that NaHCO3 is a base. (a weak one)
Which structure below contains all of the others?
DNA
gene
chromosome
nucleus
Answer:
nucleus
Explanation:
The nucleus holds all the other things, keeping them safe and confined.
Answer:
Nucleus
Explanation:
It contains DNA which contains a GENE which contains a CHROMOSOME so its NUCLEUS
what is the difference between an exothermic and endothermic reaction.
Answer:
An endothermic reaction takes in heat, but feels cold to the touch. An exothermic reaction gives off heat and feels warm to the touch because it is heating the outside objects.
Allicin is the compound responsible for the characteristic smell of Garlic. An analysis of the compound gives the following percent composition by mass; C = 44.4 percent, H = 6.21 percent. S = 39.5 percent, O = 9086 percent. Calculate its empirical formula. What is its molecular formula given that its molar mass is about 162 g?
Answer:
The empirical formula is same as the molecular formula = C6H10S2O
Explanation:
we start by dividing the percentage of each of the elements by their atomic mass
Carbon = 44.4/12 = 3.7
Hydrogen = 6.21/1 = 6.21
Sulphur = 39.5/32 = 1.234375
oxygen = 9.89/16 = 0.618125
That of oxygen is smallest so we divide all by that of oxygen
C = 3.7 / 0.618125 = 6
H = 6.21/ 0.618125 = 10
S = 1.234375/ 0.618125 = 2
Automatically, oxygen is 1
So the empirical formula is;
C6H10S2O
Let’s get its molecular formula. We multiply each of the subscript by the number;
(72 + 10 + 64 + 16)n= 162
162n = 162
n = 1
So the molecular formula is same as the empirical formula
Potassium atoms contribute one eletron to metallic bonding,but calcium atoms contribute two eletrons .Explain which metal is likely to be harder
Answer:
potassium is likely to be harder
Explanation:
because whenan atom loss electron they can form particle ion acquare stable a arrangement that loos electron can transfer to another which that also to acquaire stable
Which of he following is a secondary alkanol?
a. CH3CH2CH2OH
b. CH3CH2CH2CH2OH
c. C(CH3)3OH
d. CH3CH(OH)CH3
Answer: Thus [tex]CH_3CH(OH)CH_3[/tex] is a secondary alkanol.
Explanation:
Alkanol are compounds which contains carbons bonded by single bonds and contains hydroxy (-OH) as functional group.
Primary alkanol are those compounds which contain hydroxyl group attached a carbon which is further attached to a single carbon atom. Example: [tex]CH_3CH_2CH_2OH[/tex] and [tex]CH_3CH_2CH_2CH_2OH[/tex]
Secondary alkanol are those compounds which contain hydroxyl group attached to a carbon which is further attached to two more carbon atoms.Example: [tex]CH_3CH(OH)CH_3[/tex]
Tertiary alkanol are those compounds which contain hydroxyl group attached to a carbon which is further attached to three more carbon atoms. Example: [tex]C(CH_3)_3OH[/tex]
Thus [tex]CH_3CH(OH)CH_3[/tex] is a secondary alkanol.
the vessel in which electrolysis takes place is called
PLEASE GUYS ANSWER IT
7. What volume of a 0.10 mol/l HCl solution is needed to neutralize 10 ml of a 0.15
mol/l LiOH solution (5 points)
Answer: The volume of a 0.10 mol/l HCl solution needed to neutralize 10 ml of a 0.15 mol/l LiOH solution is 15 ml
Explanation:
To calculate the volume of acid, we use the equation given by neutralization reaction:
[tex]n_1M_1V_1=n_2M_2V_2[/tex]
where,
[tex]n_1,M_1\text{ and }V_1[/tex] are the n-factor, molarity and volume of acid which is [tex]HCl[/tex]
[tex]n_2,M_2\text{ and }V_2[/tex] are the n-factor, molarity and volume of base which is LiOH.
We are given:
[tex]n_1=1\\M_1=0.10mol/L\\V_1=?mL\\n_2=1\\M_2=0.15mol/L\\V_2=10mL[/tex]
Putting values in above equation, we get:
[tex]1\times 0.10\times V_1=1\times 0.15\times 10\\\\V_1=15mL[/tex]
Thus the volume of a 0.10 mol/l HCl solution needed to neutralize 10 ml of a 0.15 mol/l LiOH solution is 15 ml
1. Calculate the pH of a 0.35 mol/L solution of ammonia.
Answer:
Explanation:
NH3 + H2O ⇌ NH4 + OH-
0.35 0.35
-log[OH-] = -log0.35 = 0.46 = pOH
14 - 0.46 = 13.54 = pH
