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3 years ago

1. How much taller is the average person today than the average person 100 years ago?

Chemistry

1 answer:

andreev551 [17]3 years ago

4 0

5 inches I am not sure but I THINK it’s 5 inches sry if I’m wrong

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1. What is the name of the ion formed from the sulfur atom?

dolphi86 [110]

Answer:

1 sulfide

2 Fluoride

3 A

5 A

6 2

3 0

3 years ago

In a science lab, a student heats up a chemical from 10 °C to 25 °C which requires thermal energy of 30000 J. If mass of the obj

olganol [36]

Answer:

The specific heat capacity of the object is 50 J/g°C ( option 4 is correct)

Explanation:

Step 1: Data given

Initial temperature = 10.0 °C

Final temperature = 25.0 °C

Energy required = 30000 J

Mass of the object = 40.0 grams

Step 2: Calculate the specific heat capacity of the object

Q = m* c * ΔT

⇒With Q = the heat required = 30000 J

⇒with m = the mass of the object = 40.0 grams

⇒with c = the specific heat capacity of the object = TO BE DETERMINED

⇒with ΔT = The change in temperature = T2 - T2 = 25.0 °C - 10.0°C = 15.0 °C

30000 J = 40.0 g * c * 15.0 °C

c = 30000 J / (40.0 g * 15.0 °C)

c = 50 J/g°C

The specific heat capacity of the object is 50 J/g°C ( option 4 is correct)

3 0

3 years ago

Carbon-14 has a half-life of 5720 years and this is a fast-order reaction. If a piece of wood has converted 75 % of the carbon-1

Nana76 [90]

Answer:

11445.8years

Explanation:

Half-life of carbon-14 = 5720 years

First we have to calculate the rate constant, we use the formula :

7 0

3 years ago

How many grams of water can be produced from 4.6 grams of Hydrogen and 7.3 grams of Oxygen?

12345 [234]

Answer:

The answer to your question is 8.21 g of H₂O

Explanation:

Data

mas of water = ?

mass of hydrogen = 4.6 g

mass of oxygen = 7.3 g

Balanced chemical reaction

2H₂ + O₂ ⇒ 2H₂O

Process

1.- Calculate the atomic mass of the reactants

Hydrogen = 4 x 1 = 4 g

Oxygen = 16 x 2 = 32 g

2.- Calculate the limiting reactant

Theoretical yield = H₂/O₂ = 4 / 32 = 0.125

Experimental yield = H₂/ O₂ = 4.6/7.3 = 0.630

From the results, we conclude that the limiting reactant is Oxygen because the experimental yield was higher than the theoretical yield.

3.- Calculate the mass of water

32 g of O₂ ---------------- 36 g of water

7.3 g of O₂ --------------- x

x = (7.3 x 36) / 32

x = 262.8 / 32

x = 8.21 g of H₂O

4 0

3 years ago

Methanol has a normal boiling point of 64.6C and a heat of vaporization of 35.2 kJ/mol. What is the vapor pressure (in Torr) of

DENIUS [597]

Answer:

vapor pressure of methanol at 12.0C = 75.09 torr

Explanation:

Using Clausius Clapeyron equation

, we have that

ln (P2/P1)= (ΔHvap /R) (1/T1 - 1/T2)

Given

At Normal boiling point,

Temperature T1= 64.6°C = 64.6 + 273 = 337.6 K, Pressure,P1 = 1 atm

Heat of vaporization = 35.2 kJ/mol

Changing to J/mol

=35.2 x 1000= 35200 J/mol

Temperature , T2 = 12.0oC = 12 + 273 = 285 K

Using gas constant, R = 8.314 J/mol.K

ln (P2/P1)= -(ΔHvap /R) (1/T1 - 1/T2)

ln (P2/ 1 atm) = (35200 J/mol/ (8.314 J/mol.K) X( 1/337.6 - 1/285)

ln (P2/ 1 atm) =4,233.822 X (0.00296-0.003508)

ln (P2/ 1 atm) = 4,233.822468 x-0.0005466866

ln (P2/ 1 atm)= -2.31457

P2 = e^⁻2.31457 x 1 atm

P2=0.098808atm

= 0.098808atm x760 = 75.09 torr

7 0

2 years ago