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3 years ago

Which of the following statements is true?

Chemistry

1 answer:

eduard3 years ago

5 0

Answer:

Lines of latitude are used to divide Earth into 24 time zones

Explanation:

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Maple syrup, which comes from the sap of maple trees, is a mixture of water and natural sugars. It's a clear, brown liquid. It's

ANTONII [103]

C.) It's a Solution ..............

3 0

3 years ago

A car traveling at 30 m/s comes to a stop in 5 seconds. What is the acceleration of this car?

aliina [53]

Answer:

6m/s brainliest?

Explanation:

5 0

2 years ago

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A 1.00 g sample of octane (C8H18) is burned in a bomb calorimeter with a heat capacity of 837J∘C that holds 1200. g of water at

lubasha [3.4K]

Answer:

The heat of combustion for 1.00 mol of octane is -5485.7 kJ/mol

Explanation:

Step 1: Data given

Mass of octane = 1.00 grams

Heat capacity of calorimeter = 837 J/°C

Mass of water = 1200 grams

Temperature of water = 25.0°C

Final temperature : 33.2 °C

Step 2: Calculate heat absorbed by the calorimeter

q = c*ΔT

⇒ with c = the heat capacity of the calorimeter = 837 J/°C

⇒ with ΔT = The change of temperature = T2 - T1 = 33.2 - 25.0 : 8.2 °C

q = 837 * 8.2 = 6863.4 J

Step 3: Calculate heat absorbed by the water

q = m*c*ΔT

⇒ m = the mass of the water = 1200 grams

⇒ c = the specific heat of water = 4.184 J/g°C

⇒ ΔT = The change in temperature = T2 - T1 = 33.2 - 25 = 8.2 °C

q = 1200 * 4.184 * 8.2 = 41170.56 J

Step 4: Calculate the total heat

qcalorimeter + qwater = 6863.4 + 41170. 56 = 48033.96 J = 48 kJ

Since this is an exothermic reaction, there is heat released. q is positive but ΔH is negative.

Step 5: Calculate moles of octane

Moles octane = 1.00 gram / 114.23 g/mol

Moles octane = 0.00875 moles

Step 6: Calculate heat combustion for 1.00 mol of octane

ΔH = -48 kJ / 0.00875 moles

ΔH = -5485.7 kJ/mol

The heat of combustion for 1.00 mol of octane is -5485.7 kJ/mol

8 0

2 years ago

Scientists use _____ as chemical symbols. dots letters shapes lines

defon

Answer:

Letters

Explanation:

6 0

3 years ago

Read 2 more answers

(CO2) (O2) (He) (N2) (CH4) (Imagine these are balloons with the specified gas inside)

valentina_108 [34]

Answer:

Highest speed: He

Lowest speed: CO2

Explanation:

The rms speed (average speed) of the molecules/atoms in an ideal gas is given by:

$v=\sqrt{\frac{3RT}{M}}$

where

R is the gas constant

T is the absolute temperature of the gas

M is the molar mass of the gas, which is the mass of the gas per unit mole

From the equation, we see that at equal temperatures, the speed of the molecules in the gas is inversely proportional to the molar mass: the higher the molar mass, the lower the speed, and vice-versa.

In this problem, we have 5 gases:

(CO2) (O2) (He) (N2) (CH4)

Their molar mass is:

CO2: 44 g/mol

O2: 16 g/mol

He: 4 g/mol

N2: 14 g/mol

CH4: 16 g/mol

The gas with lowest molar mass is Helium (He): therefore, this is the gas with greatest average speed.

The gas with highest molar mass is CO2: therefore, this is the gas with lowest average speed.

8 0

3 years ago