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3 years ago

If a fingerprint is discovered on a dark service, what color fingerprint powder might be used?

1 answer:

8 0

Black and Grey both work but Black is the most popular choice to get the greatest contrast between the print and a white surface

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Write a reaction to describe the behavior of the following substances in water. please include all phases.

lorasvet [3.4K]

3NF3 + 5H2O → HNO3 + 2NO + 9HF

Nitrogen fluoride reacts with water to produce nitric acid, nitric oxide, and hydrogen fluoride. The reaction slowly takes place in a boiling solution.

CH2CH2 + H2O → CH3CH2OH

Ethylene is a hydrocarbon with water that creates ethanol and ethanol is an alcohol

4 0

3 years ago

Can you please help me (50 points)

Anna35 [415]

Answer:

P=15

N=59

Explanation:

Pic is blurry but I based my answer on bottom number being 74

4 0

2 years ago

A 1.00 L volume of HCl reacted completely with 2.00 L of 1.50 M Ca(OH)2 according to the balanced chemical equation below. 2HCl

Zigmanuir [339]

The first step is to find the number of moles of OH⁻ that reacted with the HCl. To do this multiply 2.00L by 1.50M to get 3 moles of Ca(OH)₂. Then you multiply 3 by 2 (there are 2 moles of OH⁻ per every 1 mole of Ca(OH)₂) to get 6 moles of OH⁻. That means that you needed 6 moles of HCl since 1 mole of HCl contains 1 mole of H⁺ and equal amounts H⁺ and OH⁻ reacted with each other. To find the molarity of the HCl solution you need to divide 6mol by 1L to get 6M. Tat means that the concentration of the acid was 6M.

I hope this helps. Let me know if anything was unclear.

5 0

3 years ago

Read 2 more answers

Unit: Chemical Quantities

Vaselesa [24]

Answer:

(See explanation for further details)

Explanation:

1) The quantity of moles of sulfur is:

$n = \frac{1.20\times 10^{24}\,atoms}{6.022\times 10^{23}\,\frac{atoms}{mol} }$

$n = 1.993\,moles$

2) The number of atoms of helium is:

$x = (1.5\,moles)\cdot \left(6.022\times 10^{23}\,\frac{atoms}{mole} \right)$

$x = 9.033\times 10^{23}\,atoms$

3) The quantity of moles of carbon monoxide is:

$n = \frac{4.15\times 10^{23}\,molecules}{6.022\times 10^{23}\,\frac{molecules}{mol} }$

$n = 0.689\,moles$

4) The number of molecules of sulfur dioxide is:

$x = (2.25\,moles)\cdot \left(6.022\times 10^{23}\,\frac{molecules}{mole} \right)$

$x = 1.355\times 10^{24}\,molecules$

5) The quantity of moles of sodium chloride is:

$n = \frac{2.4\times 10^{23}\,molecules}{6.022\times 10^{23}\,\frac{molecules}{mol} }$

$n = 0.399\,moles$

6) The number of formula units of magnesium iodide is:

$x = (1.8\,moles)\cdot \left(6.022\times 10^{23}\,\frac{f.u.}{mole} \right)$

$x = 1.084\times 10^{24}\,f.u.$

7) The quantity of moles of potassium permanganate is:

$n = \frac{3.67\times 10^{23}\,f.u.}{6.022\times 10^{23}\,\frac{f.u.}{mol} }$

$n = 1.214\,moles$

8) The number of molecules of carbon tetrachloride is:

$x = (0.25\,moles)\cdot \left(6.022\times 10^{23}\,\frac{molecules}{mole} \right)$

$x = 1.506\times 10^{23}\,molecules$

9) The quantity of moles of aluminium is:

$n = \frac{3.67\times 10^{23}\,atoms}{6.022\times 10^{23}\,\frac{atoms}{mol} }$

$n = 0.609\,moles$

10) The number of molecules of oxygen difluoride is:

$x = (3.52\,moles)\cdot \left(6.022\times 10^{23}\,\frac{molecules}{mole} \right)$

$x = 2.120\times 10^{24}\,molecules$

3 0

4 years ago

Calculate the number of molecules in 210 grams of H2O

spin [16.1K]

H2O=18.01g/mole. 210g divided by 18.01g/mole=11.653mole. 1 mole has 6.22x10^23 molecules. So there is 11.653x(6.22x10^23) molecules. Just multiply 11.653 by 6.22. Then put it as answerx10^23 molecules

4 0

3 years ago