Why do objects appear to move across the sky

Using the periodic table, determine the number of PROTONS for the element Li

KIM [24]

The number of protons for element Li is 3

4 0

3 years ago

Please help!!!!

Tomtit [17]

Answer 1) Option D : Discrete

Explanation : As in the example the scientist studies about the effects of growing human populations on the biodiversity which is found in a region, and where each region was selected had a different population density of humans from 1 to 10 million per 10 square miles. Then in each region the number of different species that can be found was recorded. So here the numerical data was collected for different regions. So, we can conclude it as discrete because when the variable takes on a countable number of values it is called as discrete.

Answer 2) Option D : The entertainment industry

Explanation : When people had enough time and money with them there was no need of creating the communications industry as it was a need not a luxurious thing. With the creation of Internet industry it is somewhat irrelevant. They had enough of time and money so building a labor industry seems to be a lame choice. So, the option of entertainment industry suits the best.

6 0

3 years ago

Read 2 more answers

True or false: You must make observations and conduct research prior to creating a hypothesis.

bekas [8.4K]

Answer:

true

Explanation:

...................

8 0

3 years ago

What is the bond between a posative and a negative ion called

guajiro [1.7K]

Answer:

Your answer would be Ionic bond.

5 0

3 years ago

A power plant is driven by the combustion of a complex fossil fuel having the formula C11H7S. Assume the air supply is composed

AlekseyPX

(a) 4C_11 H_7S + 55O_2 → 44CO_2 + 14H_2O + 4SO_2 + 20.68N_2;

(b) 4C_11 H_7S + 66O_2 → 44CO_2 + 14H_2O + 4SO_2 + 248.2N_2 + 11O_2;

(c) 23 900 kg air; (d) air:fuel = 10.2; (e) air:fuel = 12.2:1

(a) Balanced equation including N_2 from air

The balanced equation ignoring N_2 from air is

4C_11 H_7S + 55O_2 → 44CO_2 + 14H_2O + 4SO_2

Moles of N_2 =55 mol O_2 × (3.76 mol N_2/1 mol O_2) = 206.8 mol N_2

Including N_2 from air, the balanced equation is

4C_11 H_7S + 55O_2 → 44CO_2 + 14H_2O + 4SO_2 + 206.8N_2

(b) Balanced equation for 120 % stoichiometric combustion

Moles of O_2 = 55 mol O_2 × 1.20 = 66.00 mol O_2

Excess moles O_2 = (66.00 – 55) mol O_2 = 11.00 mol O_2

Moles of N_2 = 66.00 mol O_2 × (3.76 mol N_2/1 mol O_2) = 248.2 mol N_2

The balanced equation is

4C_11 H_7S + 66O_2 → 44CO_2 + 14H_2O + 4SO_2 + 248.2N_2 + 11O_2

(c) Minimum mass of air

Moles of O_2 required = 1700 kg C_11 H_7S

× (1 kmol C_11 H_7S/185.24 kg C_11 H_7S) × (55 kmol O_2/4 kmol C_11 H_7S)

= 126.2 kmol O_2

Mass of O_2 = 126.2 kmol O_2 × (32.00 kg O_2/1 kmol O_2) = 4038 kg O_2

Mass of N_2 required = 126.2 kmol O_2 × (3.76 kmol N_2/1 kmol O_2)

× (28.01 kg N_2/1 kmol N_2) = 13 285 kg N_2

Mass of air = Mass of N_2 + mass of O_2 = (4038 + 13 285) kg = 17 300 kg air

(d) Air:fuel mass ratio for 100 % combustion

Air:fuel = 17 300 kg/1700 kg = 10.2 :1

(e) Air:fuel mass ratio for 120 % combustion

Mass of air = 17 300 kg × 1.20 = 20 760 kg air

Air:fuel = 20 760 kg/1700 kg = 12.2 :1

6 0

3 years ago