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12. Chubchub runs a 440m lap in 1.2 minutes. How many laps will Chubchub

Svet_ta [14]

Answer:

the number of laps in the case when he run for 50 minutes is 18,333.33

Explanation:

The computation of the number of laps in the case when he run for 50 minutes is shown below:

Given that

He runs 440m lap in 1.2 minutes

So in 50 minutes he can have laps of

= 440 × 50 ÷ 1.2

= 18,333.33 laps

hence, the number of laps in the case when he run for 50 minutes is 18,333.33

3 0

3 years ago

Carbonic acid dissolves limestone and other rocks. This is an example of _____. chemical errosion

Jet001 [13]

Carbonic acid dissolves limestone and other rocks. This is an example of chemical erosion. An example is in the caves. Caves are formed where rainwater as it falls through the atmosphere absorbs carbon dioxide. The carbon dioxide makes the rain acidic to react it with the limestone bedrock. The rainwater is absorbed by the soil into the ground. Then as it enters through the soil, the rainwater will absorb more carbon dioxide that is produced by the decomposers. The carbon dioxide with water reacts to form carbonic acid. The carbonic acid will react to limestone and dissolves it slowly. As the space become larger, water can enter into it.

8 0

3 years ago

EASY 100 POINTS, WILL MARK BRAINLEST, 2 QUESTIONS, SHOW YOUR WORK OR NO POINTS

SVETLANKA909090 [29]

Answer:

Explanation:

1. Please provide the enthalpy info - I will work on it with the info

2.

i) Reaction a should be modified to match the number of S in equation:

2S + 2O2 -> 2SO2 deltaH = -370kJ

ii) Reaction b should be written reversely to match the reactants of SO2:

2SO2 + O2 -> 2SO3 deltaH = 256kJ

iii) Adding the equations together:

2S + 3O2 -> 2SO3

iv) Enthalpy of the combined reaction = -370+256 = -114kJ

It is negative so the reaction is exothermic.

5 0

3 years ago

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What mass of butane in grams is necessary to produce 1.5×103 kj of heat what mass of co2 is produced?

kari74 [83]

The heat of reaction (i.e. combustion) of butane ( $C_{4} H_{10}$ ) when reacted with oxygen ( $O_{2}$ )  is -2658 kJ/mol butane, and the chemical reaction is given by:

$C_{4} H_{10}$ + $\frac{13}{2} O_{2}$ ---> $4 CO_{2}$ + $5 H_{2}O$

The mass of butane required in the reaction is based on the heat produced by the reaction, which is given to be -1,500 kJ. The minus sign is added because the reaction releases heat (exothermic), which means that the products are in a "lower energy state" than the reactants.

Dividing this with the heat of reaction per mole of butane reacted would give the number of moles butane required. Then, multiplying the answer with the molar mass of butane which is 58 grams/mole, will give the mass of butane required.

Moles of butane = [(-1,500 kJ)/(-2658 kJ/mol butane)]
Moles of butane = 0.5643 moles butane

Mass of butane  = 0.5643 moles butane * 58 grams/mol butane
Mass of butane = 32.73 grams butane

The mass of carbon dioxide ( $CO_{2}$ ) can be determined by multiplying the moles of butane ( $C_{4} H_{10}$ ) with the mole ratio of ( $CO_{2}$ ) produced to the ( $C_{4} H_{10}$ ) reacted, and then with the molar mass of ( $CO_{2}$ ), which is 44 grams/mole.

Mass of carbon dioxide produced
= 0.5643 moles butane * [4 moles $CO_{2}$ / 1 mole $C_{4} H_{10}$ ] * 44 grams/mole $CO_{2}$

Mass of carbon dioxide produced
= 99.32 grams $CO_{2}$

Thus, the mass of butane required is 32.73 grams, and the mass of carbon dioxide produced from the reaction of this amount of butane is 99.32 grams.

4 0

3 years ago

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Drag the types of electromagnetic waves to place them in order of increasing frequency.

DanielleElmas [232]

Answer: UV Light is the highest!

Explanation:

Ultraviolet Light has the highest frequency between the three, Visible Light would stay in the middle since its in the middle of the spectrum, thus making Infrared the lowest.

7 0

3 years ago

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