answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Naily [24]
2 years ago
5

Which of the following factors used in a dimensional analysis calculation have a finite number of significant figures (in other

words, they are not exact numbers) that might limit the precision of the calculated value?
A. A conversion factor for time of (60 min/1 hour)
B. A conversion factor for distance of (1000 m/1 km)
C. A measurement of speed equaling (27.7 km/hour)
D. None of the above
Chemistry
1 answer:
lys-0071 [83]2 years ago
8 0

Answer: Option C

A measurement of speed equaling (27.7 km/hour)

Explanation:

It is measurement of speed equaling (27.7 km/hour) because it is a factor used in dimensional analysis because it is a problem solving method that involve the use of number or expression which can be multiplied without affecting or causing a change in the value of the expression.

27.7km/he is not the exact number that can limit the precision of the calculated value or accurate value.

You might be interested in
What is the mass of 22.4 L of H2 at STP?
Vanyuwa [196]

A. 1.01 is the right answer

Since

The formula is Pv= nRT

P=1 atm

V= 22.4 L

N= x

r= 0.0821

t = 273 k (bc it’s standard temperature)

So (1)(22.4)=(x)(0.0821)(273)

X= 1.001

7 0
2 years ago
Read 2 more answers
The table above summarizes data given to a student to evaluate the type of change that took place when substance X was mixed wit
Tamiku [17]

The question is incomplete, the complete question is;

The table above summarizes data given to a student to evaluate the type of change that took place when substance X was mixed with water. The student claimed that the data did not provide enough evidence to determine whether a chemical or physical change took place and that additional tests were needed. Which of the following identifies the best way to gather evidence to support the type of change that occurred when water and Xwere mixed?

A. Measuring the melting point of the mixture of water and X

B. Adding another substance to the mixture of water and X to see whether a solid forms

C Measuring and comparing the masses of the water,  X, and the mixture of water and X

D Measuring the electrical conductivities of X and the mixture of water and X

Answer:

D Measuring the electrical conductivities of X and the mixture of water and X

Explanation:

Unfortunately, I am unable to reproduce the table here. However, from the table,  the temperature of the of the mixture of the solid X and water was 101.6°C. This is above the boiling point of water and way below the temperature of the solid X.

This goes a long way to suggest that there was some kind of interaction between the water and X which accounted for the observed temperature of the system of X in water.

The only way we can be able to confirm if X actually dissolved in water is to measure the conductivity of the water. dissolved solids increase the conductivity of water.

6 0
2 years ago
Suppose you wanted to make a buffer of exactly ph 7.00 using kh2po4 and na2hpo4. if the final solution was 0.10 m in kh2po4, wha
OleMash [197]

Answer:- 0.138 M

Solution:- The buffer pH is calculated using Handerson equation:

pH=pKa+log(\frac{base}{acid})

KH_2PO_4 acts as a weak acid and Na_2HPO_4 as a base which is pretty conjugate base of the weak acid we have.

The acid hase two protons(hydrogen) where as the base has only one proton. So, we could write the equation as:

H_2PO_4^-\rightleftharpoons H^++HPO_4^-^2

Phosphoric acid gives protons in three steps. So, the above equation is the second step as the acid has only two protons and the base has one proton.

So, we will use the second pKa value. The acid concentration is given as 0.10 M and we are asked to calculate the concentration of the base to make a buffer of exactly pH 7.00.

Let's plug in the values in the equation:

7.00=6.86+log(\frac{base}{0.10})

7.00-6.86=log(\frac{base}{0.10})

0.14=log(\frac{base}{0.10})

Taking antilog:

10^0^.^1^4=\frac{base}{0.10}

1.38=\frac{base}{0.10}

On cross multiply:

[base] = 1.38(0.10)

[base] = 0.138

So, the concentration of the base that is Na_2HPO_4 required to make the buffer is 0.138M.

5 0
2 years ago
Summarize the process a scientist goes through to come up with a<br> satisfactory solution.
maria [59]
Guess and check, test, trial and error, completion.
6 0
2 years ago
Match the following names of glassware with what you would use them for.(1) Glassware used to accurately transfer small volumes.
Andrei [34K]

Answer:

(1)=(A), (2)=(B), (3)=D, (4)=C, (5)=E, (6)=F

Explanation:

(1) Glassware used to accurately transfer small volumes = (A) Graduated pipette, that is basically a glass tube with graduation of different volumes to be dispensed.

(2) Glassware used to accurately transfer a small, single volume = (B) Volumetric pipette, that is a glass tube with a central glass bulb and is used to dispense accurately an unique volume of liquid everytime.

(3) Glassware to deliver a volume not known in advance = (D) Buret (or burette), that is used to dispense slowly a volume of liquid when a titration process is needed

(4) Glassware best used when greater access to the contents is needed = (C) Beaker, that is basically a very open glass cylinder with a spout

(5) Glassware used to prevent splashing or evaporation = (E) Erlenmeyer flask, that has a small open at the top and is useful when the liquid needs to be swirled as, for example, during a titration.

(6) Glassware used to make accurate solutions = (F) Volumetric flask, that has a long slim neck that provides a higher accuracy when a exact volume of liquid needs to be used for preparation of a solution.

8 0
2 years ago
Other questions:
  • if the solubility of a gas is 7.5 g/L at 404 pressure, what is the solubility of the gas when the pressure is 202 kPa?
    9·2 answers
  • if the fundamental frequency of a certain string is 84 hz, what is the frequency of the second harmonic? 42 hz 84 hz 126 hz 168
    13·2 answers
  • Using the idea of electronegativity difference for predicting polarity of bonds and considering the shape of the following molec
    10·1 answer
  • How many molecules are in 79g of fe2o3
    12·1 answer
  • A 0.0035 M aqueous solution of a particular compound has pH = 2.46. The compound is (A) a weak base (B) a weak acid (C) a strong
    15·1 answer
  • When an athlete gets hurt they apply sometimes an instant cold pack to the injury. The instant cold pack works by mixing two che
    13·1 answer
  • Leaded gasoline contains an additive to prevent engine knocking. On analysis, the additive compound is found to contain carbon,
    13·1 answer
  • What is the theoretical yield of aluminum that can be produced by the reaction of 60.0 g of aluminum oxide with 30.0 g of carbon
    12·1 answer
  • The concentration of hydrogen peroxide in a hair bleach is 0.050 mol dm–3. Use your answer from (b) to calculate the dilution fa
    7·1 answer
  • During the analysis, 0.00905 mol H2O is formed. Calculate the amount (mol) H in 0.00905 mol H2O.
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!