1answer.
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
Assoli18 [71]
3 years ago
10

A race car is driven by a professional driver at 99 . What is this speed in and ? 1 mile = 1.61 kilometers 1 hour = 60 minutes E

xpress the answers to the correct number of significant figures. The speed is equivalent to , or .
Chemistry
1 answer:
slavikrds [6]3 years ago
4 0

Answer: The speed is equivalent to <u>159.39 kilometers per hour </u>or <u>2.65 kilometers per minute.</u>

Explanation:

Given, The speed of a race car = 99 miles/ hour

To convert the speed into  kilometers per hour and kilometers per minute

Since   1 mile = 1.61 kilometers

So, Speed of car = (99 ) x (1.61 )

= 159.39 kilometers per hour.

Also, 1 hour = 60 minutes

Then, Speed of car = (159.39) ÷60

= 2.6565≈2.65 kilometer per minute.

Hence, the speed is equivalent to <u>159.39 kilometers per hour </u>or <u>2.65 kilometers per minute.</u>

You might be interested in
three molecules of oxygen react with four molecules of hydrogen to produce water molecules write a balanced chemical equation
mixer [17]

Answer:

ExpC

H

4

+  

2

O

2

 

→

 

C

O

2

+  

2

H

2

O

This is the balanced reaction equation for the combustion of methane.

Explanation:

The Law of Conservation of Mass basically states that matter can neither be created nor destroyed. As such, we must be able to show this in our chemical reaction equations.

If you look at the equation above, you'll see an arrow that separates the reaction equation into two parts. This represents the direction of the reaction.

To the left of the arrow, we have our reactants.

To the right of the arrow, we have our products.

The quantity of each individual element in the left must equal the quantity of each individual element in the right.

So if you look below, you'll see the unbalanced equation, and I'll try to explain how to balance the reaction.

C

H

4

+  

O

2

 

→

 

C

O

2

+  

H

2

O

Our reactants in this equation are  

C

H

4

and  

O

2

.

Our next step is to break these down into individual atoms.

We have:

1 C atom, 4 H atoms & 2 O atoms.

If you're confused by this, look to see the little number to the bottom right of each element, the subscript, and it tells you how many of each atom are in the molecule. Make sense?

Now we look to the other side of the equation.

Here we see our products are  

C

O

2

+  

H

2

O

Again, we break these down into individual atoms again.

We have:

1 C atom, 2 H atom, 3 O atom

6 0
2 years ago
The average C - H bond energy in CH4 is 415 kJ / mol. Use the following data to calculate the average C - H bond energy in ethan
sertanlavr [38]

Answer and Explanation:

ΔH = (Bond energies of the products) - (Bond Energies of the reactants)

a) C2H6 + H2 ----> 2CH4 ΔH = -65.07 KJ/mol

Bond energy of product = 2×Bond energy of CH4 =2 × (4 (C-H)) =2 × 4 × 415 = 3320 KJ/mol

Bond energy of reactants = Bond energy of C2H6 + Bond energy of H2

Bond energy of C2H6 = (C-C) + 6(C-H) = 347 + 6(C-H)

Bond energy of H2 = (H-H) = 432 KJ/mol

-65.07 = 3320 - (Bond energy of C2H6 + 432)

Bond energy of C2H6 = 3320-432+65.07 = 2953.07 KJ/mol

Bond energy of C2H6 = (C-C) + 6(C-H) = 347 + 6(C-H) = 2953.07

(C-H) = (2953.07 -347)/6 = 434.345 KJ/mol

b) C2H4 + 2H2 ------> CH4 ΔH = -202.21 KJ/mol

Bond energy of product = 2×Bond energy of CH4 =2 × (4 (C-H)) =2 × 4 × 415 = 3320 KJ/mol

Bond energy of reactants = Bond energy of C2H4 + (2 × Bond energy of H2)

Bond energy of C2H4 = (C=C) + 4(C-H) = 614 + 4(C-H)

(2 × Bond energy of H2) = 2 × 432 = 864 KJ/mol

-202.21 = 3320 - (Bond energy of C2H4 + 864)

Bond energy of C2H4 = 3320+202.21-864 = 2658.1 KJ/mol

Bond energy of C2H4 = (C=C) + 4(C-H) = 614 + 4(C-H) = 2658.1

(C-H) = (2658.1 - 614)/4 = 511.05 KJ/mol

c) C2H2 + 3H2 ------> 2CH4 ΔH = -376.74 KJ/mol

Bond energy of product = 2×Bond energy of CH4 =2 × (4 (C-H)) =2 × 4 × 415 = 3320 KJ/mol

Bond energy of reactants = Bond energy of C2H2 + (3 × Bond energy of H2)

Bond energy of C2H = (triple bond Carbon to Carbon) + 2(C-H) = 839 + 2(C-H)

(3 × Bond energy of H2) = 3 × 432 = 1296 KJ/mol

-376.74 = 3320 - (Bond energy of C2H2 + 1296)

Bond energy of C2H2 = 3320+376.74-1296 = 2400.74 KJ/mol

Bond energy of C2H2 = (triple bond Carbon to Carbon) + 2(C-H) = 839 + 2(C-H) = 2400.74

(C-H) = (2400.74 - 839)/2 = 780.87 KJ/mol

QED!!!

6 0
3 years ago
Find the mass of an object with a density of 2.01g/mL and a volume of 3.77mL
oee [108]

Answer:

<h2>7.58 g</h2>

Explanation:

The mass of a substance when given the density and volume can be found by using the formula

mass = Density × volume

From the question we have

mass = 2.01 × 3.77 = 7.5777

We have the final answer as

<h3>7.58 g</h3>

Hope this helps you

3 0
3 years ago
Which shows two structures that are made mostly of metal?
lesya [120]

Answer:

The bell and the Eiffel tower

4 0
2 years ago
Read 2 more answers
4 Recall What holds ionic compounds<br> together?
Kazeer [188]

Answer:

The opposite charges of the atoms hold the atoms together. One atom can have a positive charge while the other can have a negative charge and this causes an electrostatic attraction causing the atoms to stick to each other like glue. For example, two magnets, can only be attracted to each other when one side of the magnet has a "-" while the other magnet on one side has a "+". They are attracted to each other by these varying charges. The same applies to ionic compounds which are held together by the varying charges of the ions.

7 0
3 years ago
Other questions:
  • 4. When benzene reacts with 1-chloro-2,2-dimethylpropane (neopentyl chloride) in the presence of aluminum chloride, the major pr
    11·1 answer
  • How to find limiting reagent
    15·2 answers
  • In a nuclear reaction, the energy released is equal to 8.1 x 1016 joules. Calculate the mass lost in this reaction. (1 J = 1 kg
    15·2 answers
  • HNO3 is an Arrhenius ______________ and increases the concentration of __________ when added to water.
    14·1 answer
  • Diamond is a covalently-bonded substance made of pure carbon. Each carbon atom has six total electrons so this means carbon shar
    13·2 answers
  • At the same temperature, a freshwater lake frezzes but a salt water bay does not because
    11·1 answer
  • YO SOMEONE ANSWER DIS ASAP I GOT 2 MINUTES
    12·1 answer
  • Please help me thanks
    11·2 answers
  • Determine the reducing agent in the following reaction. Explain your answer. 2 Li(s) + Fe(C2H3O2)2(aq) → 2 LiC2H3O2(aq) + Fe(s)
    14·1 answer
  • Chemical calculation. don't have to rush, take your time.
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!