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4 years ago

Use the ruler to determine the length of the line measured to the correct degree of precision. 13.2 cm 13.25 cm 130 cm 132 mm

Chemistry

2 answers:

ipn [44]4 years ago

6 0

Answer: B) 13.25 cm

Explanation: A centimeter ruler is used to measure the lengths of objects and the lengths are recorded to two decimal places.

The given numbers are 13.2 cm, 13.25 cm, 130 cm and 132 cm. 13.2 cm has only one decimal place, 13.25 cm has two decimal places, 130 and 132 cm have zero decimal places.

So, the only correct choice is 13.25 cm as it has two decimal places and so its more precised.

lapo4ka [179]4 years ago

3 0

Your answer would be 13.25cm

Hope that helps!!!

You might be interested in

In the reaction aA + bB >> dD, the lowercase letters represent?

jolli1 [7]

Answer:

Coefficient

Explanation:

Chemical equation:

aA + bB → dD

This equation shows that reaction is balanced by coefficient q,b and d.

Reactant coefficients Product Coefficient

A a D d

B b

Every balanced equation follow the law of conservation of mass.

Law of conservation of mass:

According to the law of conservation mass, mass can neither be created nor destroyed in a chemical equation.

Explanation:

This law was given by french chemist Antoine Lavoisier in 1789. According to this law mass of reactant and mass of product must be equal, because masses are not created or destroyed in a chemical reaction.

For example:

In given photosynthesis reaction:

6CO₂ + 6H₂O + energy → C₆H₁₂O₆ + 6O₂

there are six carbon atoms, eighteen oxygen atoms and twelve hydrogen atoms on the both side of equation so this reaction followed the law of conservation of mass. The numbers 6 with CO₂, 6 with H₂O and 6 with O₂ are coefficient which balance the equation.

8 0

3 years ago

The mass of a single gold atom is 3.27X10^-22 grams. How many gold Adams with there be in 57.8 mg of gold.

vichka [17]

Answer:

18 * 10^19 atoms

Explanation:

We must first convert 57.8 mg to grams.

If 1000 mg = 1g

57.8 mg = 57.8/1000 = 57.8 * 10^-3 g

Now;

If 1 gold atom has a mass of 3.27X10^-22 grams

x gold atoms have a mass of 57.8 * 10^-3 g

x = 57.8 * 10^-3 g/3.27X10^-22 g

x = 18 * 10^19 atoms

7 0

3 years ago

determine the average volume from the following volume reading: 3.00ml, 2.0ml, 2.987 x 10^-3 l, and 3.4856 ml

lesya [120]

Answer:

The average of given values is 2.1221 ml

Explanation:

Given data:

Given measurements = 3.00 ml , 2.0 ml, 2.987 × 10⁻³ml , 3.4856 ml

Average value of given measurements = ?

Solution:

Formula:

Average value = sum of all measurement / total number of measurements

2.987 × 10⁻³ml = 0.002987 ml

Now we will put the values.

Average value = 3.00 ml + 2.0 ml + 0.002987 ml+ 3.4856 ml / 4

Average value = 8.488587 ml / 4

Average value = 2.1221 ml

The average of given values is 2.1221 ml

8 0

3 years ago

Plot your values of ln(Ksp) vs. 1/T and find the slope and y-intercept of the best fit line. Use the equation for the best fit l

labwork [276]

Answer:

a) The slope of the line of best fit plot = -12629.507

b) ΔH∘ = 105 kJ

c) Intercept of the line of best fit plot = 39.099

d) ΔS∘ = 325.1 J/K

e) Option A is correct.

Solubility will increase as temperature increases, because as T increases the (−ΔH∘/RT) term becomes smaller therefore K will get larger.

f) Option D is correct. All of the options are correct.

Explanation:

The complete question is presented in the first attached image to this question. This complete question has the data readings required to plot the graph.

The second attached image has the plotted graph and the regression analysis to obtain the line of best fit.

The equation of the line of best fit obtained is

y = -12629.507x + 39.099

Comparing the given expression for the question with the equation of a straight line

ln (K) = (−ΔH∘/RT) + (ΔS∘/R)

y = mx + c

y = In K

Slope = m = (−ΔH∘/R)

x = (1/T)

Intercept = c = (ΔS∘/R)

So, to answer the question now

a) The slope of the line of best fit plot = -12629.507

b) Slope = (−ΔH∘/R)

(−ΔH∘/R) = -12629.507

But R = molar gas constant = 8.314 J/mol.K

ΔH∘ = 12629.507 × 8.314 = 105,001.721198 J = 105,002 J = 105 kJ

c) Intercept of the line of best fit plot = 39.099

d) Intercept = (ΔS∘/R)

(ΔS∘/R) = 39.099

ΔS∘ = 39.099 × 8.314 = 325.069086 J/K = 325.1 J/K

e) Do you expect the solubility of Borax to increase or decrease as temperature increases?

Solubility will increase as temperature increases, because as T increases the (−ΔH∘/RT) term becomes smaller therefore K will get larger.

f) Why was it necessary to make sure that some solid was present in the main solution before taking the samples to measure Ksp? Select the option that best explains why.

A. To make sure no more sodium borate would dissolve in solution.

B. To ensure the dissolution process was at equilibrium.

C. To make sure the solution was saturated with sodium and borate ions.

D. All of the above

Hope this Helps!!!

5 0

3 years ago

Write a rap about fossils please

givi [52]

Answer:

CHORUS 1:

Fossil rocks are in the ground tonight

They’ve been down there for a really long time

They contain the history of life

They’ve been down there for a really long time

Fossil rocks are in the ground tonight

They’ve been down there for a really long time (They’re the schist*)

They are literally on the grind

Take your hammer out and... break that

VERSE 1:

Look at the ground. Partly rock

Plus plants and animals stuck in their spot. Huh

Each new layer stackin’ up

So the oldest on the bottom and the newest on top

“So how old is your fossil, bro?”

Well it was pretty far down so it’s pretty darn old

And I dated this one, so I gots to know

It’s from 3.5 billion years ago

Yo. I got that lava flow, Volcano

Air full of particles & smoke

There goes life as they know

Now that’s a blast! But most rocks ain’t movin’ that fast

The sediment’s evidence. Like a present tellin’ us of the past

CHORUS 2:

Take your chisel out and… flake that

BREAK:

Everyday I’m Shovelin’…

Brushin’ ‘em, Brushin’ ‘em

VERSE 2:

Brush it off and hear the story of life as told through rock

The story of the earth as told through life. Now stop... do the trilobite

Continental plates (are driftin’)

Mountains in the states (upliftin’)

Tend to isolate (species)

By affecting who you mate with (believe me)

Slow moves. Long time. Push up mountains to the sky

Slow moves. Long time. Open up a great divide

Slow moves. Long time. Fossils found on either side

Fossils found they tell us why... tell the history of life....

Slow moves. Long time. Slow moves. Long time

Plates are driftin’ at ya boy. Plates are driftin’ at ya boy

Plates are driftin’ at ya boy. Now boom. There’s an asteroid

Explanation:

4 0

3 years ago

Read 2 more answers