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3 years ago

7

Can I have help with Environmental Science? Explain how a GIS can model the ways that changes in climate can influence human act

ivity. Include a specific example.
Side Note: this is for Environmental Science not chemistry

1 answer:

Sergeu [11.5K]3 years ago

6 0

Answer:

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You might be interested in

1. Imagine that you need to take a medicine that the doctor has prescribed for

soldi70 [24.7K]

Answer: Only non-polar medicines can diffuse across the membrane. non-polar drugs are lipid soluble, while polar drugs are water soluble, so polar drugs cant absorb through biological membranes.

3 0

2 years ago

A mixture of 50 wt% methane, 35 wt% ethane, and 15 wt% propane. Determeine the mole fraction of methane.

dmitriy555 [2]

Answer:

a) Molar fraction:

Methane: 67,5%

Ethane: 25,1%

Propane: 7,4%

b) Molecular weight of the mixture: 25,16 g/mol

Explanation:

with a basis of 100 kg:

Moles of methane:

500 g × $\frac{1mol}{16,04 g}$ = 31,2 moles

Mass of ethane

350 g × $\frac{1mol}{30,07 g}$ = 11,6 moles

Mass of propane

150 g × $\frac{1mol}{44,1 g}$ = 3,4 moles

Total moles: 31,2 moles + 11,6 moles + 3,4 moles = <em>46,2 moles</em>

Molar fraction of n-methane:

$\frac{31,2moles}{46,2moles}$ =67,5%

Molar fraction of ethane:

$\frac{11,6moles}{46,2moles}$ = 25,1%

Molar fraction of propane:

$\frac{3,4moles}{46,2moles}$ = 7,4%

b) Average molecular weight:

$0,5*16,04g/mol + 0,35*30,07g/mol+0,15*44,1g/mol}$ = <em>25,16g/mol</em>

I hope it helps!

5 0

3 years ago

Which of the following statements describes a liquid?

goldfiish [28.3K]

Answer:

A liquid has a definite volume but not a definite shape

6 0

2 years ago

Read 2 more answers

Which of the following is not a true statement?

Lilit [14]

Answer: 3.42 moles CO = 84.0g, is not true.

Explanation:

Moles is given by the formular; Mass / Molar Mass.

Therefore; 0.2 moles O2 = 6g is true when we multiply 32g x 0.2 = 6g approximately.

0.75 moles H2CO3 = 47g.

Molar formular for H2CO3 = 2 + 12 + 48 =62g.

If we multiply 62g (molar mass ) by 0.75moles, it gives us 47g approximately.

3.42 moles CO = 84g

molar mass of CO = 12 + 16 = 28g

Multiply 28g x 3.42 moles = 95.76g, which is not true.

8 0

3 years ago

Lead ions can be precipitated from solution with KCl according to the following reaction:

MrRa [10]

Answer:

34.48 grams = Theoretical yield

The % yield is 85.85 %

Explanation:

<u>Step 1:</u> The balanced equation

Pb2+(aq) + 2KCl(aq) → PbCl2(s) + 2K+(aq)

For 1 mole Pb2+ consumed, we need 2 moles of KCl to produce 1 mole of PbCl2 and 2 moles of K+

<u>Step 2:</u> Given data

Mass of KCl = 28.8 grams

Mass of Pb2 = 25.6 grams

Mass of dried PbCl2 = 29.6 grams

Molar mass of Pb2+ = 207.2 g/mol

Molar mass of KCl = 74.55 g/mol

Molar mass of PbCl2 = 278.1 g/mol

<u>Step 3:</u> Calculate moles of Pb2+

Moles = mass / Molar mass

Moles Pb2+ = 25.6 grams / 207.2 g/mol = 0.124 moles

<u>Step 4:</u> Calculate moles of KCl

Moles = 28.8 grams / 74.55 g/mol = 0.386 moles

<u>Step 5</u>: Calculate limiting reactant

For 1 mole Pb2+ consumed, we need 2 moles of KCl

Pb2+ is the limiting reactant. It will completely ( 0.124 moles) be consumed. There will remain 0 moles

There will react 2* 0.124 = 0.248 moles of KCl. There will remain 0.386 - 0.248 = 0.138 moles of KCl

<u>Step 6:</u> Calculate number of moles of PbCl2

For 1 mole Pb2+ consumed, we need 2 moles of KCl to produce 1 mole of PbCl2 and 2 moles of K+

For 0.124 moles of Pb2+ consumed ,there will be produced 0.124 moles of PbCl2

<u>Step 7:</u> Calculate mass of PbCl2

Mass = Numbers of moles * Molar mass

mass PbCl2 =0.124 moles * 278.1 g/mol = 34.48 grams = Theoretical yield

<u>Step 8</u>: Calculate % yield

% yield = (actual yield / theoretical yield) * 100 = (29.6 grams / 34.48 grams) *100 % = 85.85 %

The % yield is 85.85 %

8 0

3 years ago