Answer:
A. Distance = 18 m
time = 2 hr
speed = 9 m/hr
Explanation:
Speed is the same thing as velocity.
Velocity = distance/time
18m/2hr = 9m/hr
For choice B, the numbers are right, but the units are mixed (minutes were changed to hours)
Most strong electrolyte solutions are not ideal so that the measured value of the van't Hoff factor i is _____ than expected from the formula of the compound. This is because ions in solution are not totally isolated from each other, but remain clustered together to form an ionic atmosphere. This _____ the effective concentration of particles and therefore the measured value of i.
Answer: Van't Hoff factor, i is less than expected from the formula of the compound and this decreases the effective concentration of particles.
Explanation:
Strong electrolytes are defined as the solutions which completely dissociate into their ions.
But, most of the strong electrolytes do not dissociate completely (act ideally) but remain partially undissociated into the ions. Thus, giving a lesser number of ions in the solution than expected.
This means that the Van't Hoff factor, i which denotes the number of ions is less than expected.
As fewer ions are released in the solution, the concentration of the solution is expected to decrease.
Hence, van't Hoff factor, i is less than expected from the formula of the compound and this decreases the effective concentration of particles.
To determine whether Gd-daa3 is selective for Zn2 , researchers compared relaxivity measurements of Gd-daa3 in the presence of different cations. Varying amounts of XCl2 (where X is Zn, Ca, or Mg) were added to a 0.1 mM solution of Gd-daa3 plus 10 mM KCl/10 mM HEPES buffer at pH 7.4. What is the most appropriate control for this experiment
Add 250.0mL to 5.00mL and round off the answer
Answer:
255mL
Explanation:
(250.0 + 5.00)mL = 255.00mL
255mL
Which yield comes from measurements obtained during a real experiment?
A) actual yield
B) theoretical yield
C) percent yield
Answer:
A) actual yield
Explanation:
Actual yield is the amount of product that is actually produced in a chemical reaction.
Theoretical yield is the amount of product expected based on stoichiometry.
Per cent yield is the actual yield over the theoretical yield.
When you perform a stoichiometry calculation, you are determining the ...
A) actual yield
B) theoretical yield
C) percent yield
Answer:
B. Theoretical yield
Explanation:
Hope its help:)
why couple use a method of birth control
Answer:
because it will control the birth of a child which can happen alot being overpopulated in the country or world. It also can mange their life and create a small and happy and healthy family.Also the child can get more love and support from their parents if they have less children and it wont be a taruma for the couple as well. because growing a child can be expensive time costly and really hard.
plz mark me as a brainlest a and thanks my answer
Explanation:
and btw i think the subject should be biology not chemestry
Write the balanced chemical equation for the reaction between aqueous sodium carbonate and
aqueous nitric acid.
Answer:
2HNO3 (aq) + Na2CO3 (aq) → 2NaNO3 (aq) + CO2 (g) + H2O (l)
Explanation:
This question is asking to write and balance an equation between between aqueous sodium carbonate (Na2CO3) and aqueous nitric acid (HNO3). The equation is as follows:
HNO3 (aq) + Na2CO3 (aq) → NaNO3 (aq) + CO2 (g) + H2O (l)
However, this equation is not balanced as the number of atoms of each element must be the same on both sides of the equation. To balance the equation, one will make use of coefficients as follows:
2HNO3 (aq) + Na2CO3 (aq) → 2NaNO3 (aq) + CO2 (g) + H2O (l)
To what extent do covalent compounds conduct electricity?
always
usually
rarely
never
The answer is never because there's no electricity
Answer:
never is the correct answer
Explanation:
The balanced equation below represents the reaction between carbon and hydrogen to produce
ethane.
2C(s) + 3H2(g) → C2H6(g) + energy
Determine the number of moles of O2(g) needed to completely react with 8.0 moles of CO(g).
Please help!!!
Answer:
4.0 moles
Explanation:
Based on the given reaction between carbon and hydrogen, the equation of the reaction between O₂ and CO is as follows:
2CO(g) + O₂(g) → 2CO₂(g)
The number of moles of O₂ needed to completely react with 8.0 moles of CO can be calculated knowing that 2 moles of CO react with 1 mol of O₂:
[tex] n_{O_{2}} = \frac{1 mol O_{2}}{2 moles CO}*8.0 moles CO = 4.0 moles O_{2} [/tex]
Therefore, the number of moles of O₂ needed is 4.0.
I hope it helps you!
Substances that have a pH
7 are considered acidic.
Answer:
False because pH value below 7 are considered acidic.
Answer:
Any solution that has a pH of less than 7 is considered acidic, and anything above a pH of 7 is basic .
Explanation:
A scientist performs a cutting-edge experiment with exciting results. What
should the scientist do next?
A. Develop a theory based on the results
O B. Repeat the experiment
C. Perform new experiments based on the results
D. Publish the results
Answer:
B
Explanation:
It's B because the first trial of an experiment may not always be right so you want to run multiple trials
Read the following reactions.
Reaction 1: NaCl(s) -> Na+ (aq) + CI-
Reaction 2: N2 + 3H2 -> 2NH3
Which reaction leads to an increase in entropy?
Only Reaction 1
Only Reaction 2
Both Reaction 1 and 2
Neither Reaction 1 nor 2
Answer:
Only Reaction 1
Explanation:
In reaction 1, there is a change in state from solid to liquid. Hence, there is an increase in number of ways particles and their energies could be arranged. As a result, entropy increases.
In reaction 2, there is a decrease in amount of gas particles (4 mol to 2 mol). Hence there is a decrease in the number of ways particles and their energies could be arranged. As a result entropy decreases
Only Reaction 1 will lead to an increase in entropy.
What is Entropy?This is the degree of disorderliness or randomness of a particle and it is
denoted as S.
In states of matter, conversion from solid to other states such as liquid
brings about increase in entropy which is why only reaction 1 experienced
this phenomenon.
Read more about Entropy here https://brainly.com/question/6364271
Describe the trends in properties of chlorides across period 3 .Their formula .Their state .Their volatility .Their structure .The ph of aqueous chloride solution
Answer:
See explanation
Explanation:
Period 3 elements include; Na, Mg, Al, Si, P,S,Cl and Ar
Across the period, the chlorides of the elements change from solid to gas. The chlorides of metals are solid while the chlorides of non metals are gaseous.
Also, the chlorides become more volatile across the period. The formulas of the chlorides change from MCl to MCl2 to MCl3 to MCl4, MCl5 and MCl6 respectively across the period where M is a period 3 element.
The pH of the solutions of chlorides of period 3 elements change from neutral to acidic across the period. The pH of the chlorides of metals are neutral while the chlorides of the nonmetals usually yield acid solutions.
Al + AgNO3 -> Al(NO3)3 + Ag. As a balanced equation
Answer:
Al + 4AgNO3 >>Al(NO3)3+ 3Ag
Explanation:
the number of moles of No3 of the products is 3 therefore we have to balance the reactants by adding 3 before the "AgNO3" which also leades us to adding 3 mols to Ag on the products side
balance equation
Mg + HN03 -> Mg (N03)2 + N0 + H20
2 moles of sodium chloride are dissolved in 8 liters of water. What is its molarity (M) ?
Answer:
0.25M
Explanation:
Since molarity is defined as the amount of substance in 1 liter of a solution, and amount in chemistry refers to the number of moles, molarity can be found using the equation below:
Molarity= number of moles ÷ volume in liters
Given: number of moles= 2
Volume= 8L
∴ Molarity of NaCl
= 2 ÷8
= 0.25M
what is photosynthesis?
Answer:
the process by which green plants and some other organisms use sunlight to synthesize nutrients from carbon dioxide and water. Photosynthesis in plants generally involves the green pigment chlorophyll and generates oxygen as a by-product.
Explanation:
Hope it helps
[tex]\bf{\underline{\underline{PHOTOSYNTHESIS }} }[/tex]
Photosynthesis is a chemical reaction that takes place inside a plant, producing food for the plant to survive.Carbon dioxide, water and light are all needed for photosynthesis to take place.Photosynthesis happens in the leaves of a plant.Which cannot be chemically broken down into simpler substances?
compound
element
solution
mixture
Answer:
B.
Explanation:
elements
Identify the principle of separation.
i. raw rice and lentils
ii. sulphur and iron filings
ii. sand and sawdust
iv. oil and water
v. ammonium chloride, salt and sand
Explanation:
I. husking
ii. use magnet
III. husking
iv. floatation
v. Fractional distillation
A haloalkane 'X' if heated with sodium metal in presence of dry ether produces
2,3 - dimethyl butane
as major product
Identify x with chemical reaction.
Answer:
2 halo - propane
Explanation:
We are told that a halo alkane is heated with sodium in the presence of dry ether to produce 2,3 - dimethyl butane.
Now, according to Wurtz reaction this formation from heating with sodium in the presence of dry ether is done by 2 alkyl halides in the form of;
2RX + 2Na → R−R + 2Na+X−
Now, formula for 2,3 dimethyl butane is (CH₃)₂CHCH(CH₃)₂
Thus, from the Wurtz reaction, we can write that;
2RX + 2Na → (CH₃)₂CH - CH(CH₃)₂ + 2Na+X−
So, R = (CH₃)₂CH
This means the original halo alkane has 3 carbon atoms and thus, we can say it is 2 halo - propane.
Calculate the volume in Liters of 15 moles of Neon gas (at STP)
I'll give brainliest. My group has been struggling to answer this. We just need a solid answer with work to pick up our grades at least.
How many grams of Al(OH)3 are produced from 3.00 g of AlCl3 with excess of NaOH?
Explanation:
here u go the Answer with the working:)
If 18.5 grams of CuCl2 react with 22.8 grams of NaNO3, what mass of NaCl can be formed?
CuCl2 + NaNO3 → Cu(NO3)2 + NaCl
12.4 g NaCl
15.7 g NaCl
16.2 g NaCl
28.4 g NaCl
Answer:
From above calculations, gives the limited amount of NaCl. So, 15.7 g of NaCl would form from given amounts of reactants.
Explanation:
thank me later
How many moles are in 9.40 grams Sodium nitrate?
A 11.0g sample of a compound containing only oxygen and carbon produce 3.0g carbon and 8.0g oxygen. Determined the empirical formula of the compound?
Answer:
Empirical formula: CO₂
Explanation:
The empirical formula is defined as the simplest ratio of atoms present in a molecule. We must convert the mass of carbon and oxygen to moles as follows:
Carbon -Molar mass: 12.01g/mol-
3.0g * (1mol / 12.01g) = 0.250 moles C
Oxygen -Molar mass: 16g/mol-
8.0g * (1mol / 16g) = 0.50 moles O
The ratio of O:C is:
0.50mol / 0.250mol = 2
That means the empirical formula is:
CO₂Explain the difference between solid liquid and gaseous states using the theoritical
Answer:
solid is the substance which is hard
liquid is the substance which we get in liquid form for example water milk etc
gases are those substance which we cannot touch and see
Which environment has lower temperatures at higher elevations?
A: Desert
B: Grassland
C: mountain
D: Swamp
Press the yellow reset button at the bottom of the simulation screen. Under Constant Parameter, select Volume. Again,
pump the pump handle once to introduce 40 to 50 gas molecules. Record the pressure in the data table.
Use the heat control to heat the gas to each of the other temperatures in the data table, and record the new pressure.
В І о
x
X
Font Sizes
A -A-3 E 3
Temperature (K)
Pressure (atm)
300
600
900
1200
1500
Answer:
300 0.24
600 0.46
900 0.70
1200 0.95
1500 1.20
Explanation: correct on behavior gasses tutorial
Which gas would effuse more slowly:
Xe
CO2
CH4
N2
N2 should be the gas to effuse more slowly
the name for the following formula C9H18 should be
O octane
O octene
O nonane
O nonene