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2 years ago

Key Concepts

Chemistry

1 answer:

ladessa [460]2 years ago

8 0

Answer:

Explanation:

Answer

It tells you what method she used and what she wanted to accomplish. She is using

an absolute dating method to study a sample of basalt

So the answer you should post is F. F and the quotation above say the same thing.

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What's the name of a wave moving along a line?

yuradex [85]

Answer:

transverse wave I believe

Explanation:

3 0

3 years ago

Read 2 more answers

To aid in the prevention of tooth decay, it is recommended that drinking water contains 0.900 ppm fluoride (F-). A) How many g o

Romashka-Z-Leto [24]

Answer:

a) 1.740 g of F- must be added to a cylindrical water reservoir

b) Grams of sodium fluoride, NaF, that contain this much fluoride:

3.84 g

Explanation:

Step 1. calculate the volume of the tank:

Volume of cylinder =

$\pi r^{2}h$ ,

Here r = radius of the cylinder = d/2

h = depth = 21.80m

$r=\frac{d}{2}$

$=\frac{3.36x10^{2}}{2}$

= 168 m

Volume =

$=\frac{22\times 168^{2}\times 21.80}{7}$

$=1.93\times 10^{6} m^{3}$

2.Convert ppm to g/m3 and Solve for mass of F-

$1ppm = 1g/m^{3}$

$0.9ppm = 0.9g/m^{3}$

Because both ppm and g/m3 are same quantity .

$g/m^{3} =\frac{mass\ of\ F-(g)}{Volume\ m^{3}}\times 10^{6}$

$0.9 =\frac{mass\ of\ F-}{1.93\times 10^{6} m^{3}}\times 10^{6}$

$mass\ of\ F- =1.740g$

mass of F- required = 1.740 g

3. Apply mole concept to calculate grams of sodium fluoride produced

mass of 1 mole of F2 = 38 g

mass of 1 mole of NaF = 42 g

(from periodic table calculate molar mass)

$2Na+F_{2}\rightarrow 2NaF$

Here 1 mole of F2 produce = 2 mole of NaF

So,

38 g of F2 produce = 2 x 42 g of NaF

38 g of F2 produce = 84 g of NaF

1 g of F2 produce = 84/38 g of NaF

1.74 g F2 produce =

$\frac {84}{38}\times 1.74$

1.74 g F2 produce = 3.84 g of NaF

3.84 g of NaF is produced

3 0

3 years ago

Which of the following statements are true about whether atoms tend to gain or lose electrons?

Dafna11 [192]

Answer:

C and D

Explanation:

Atoms with five, six or seven valance electrons gain electrons to complete the octet because it is more convenient for the atoms to gain three, two or one electron as compared to lose five, six or seven electrons. Thus atoms with five, six or seven valance electrons form negative ions by gaining electrons.

Atoms with one, two or three valance electrons lose the electrons to get complete octet because it is more convenient for the atoms to lose one two or three electrons as compared to gain the seven, six or five electrons. The atoms with one, two or three valance electrons form positive ions.

5 0

3 years ago

Explain 3 sources of carbon dioxide production and explain how the production of CO2 can lead to global warming.

prisoha [69]

Answer:

Natural sources include decomposition, ocean release and respiration. Human sources come from activities like cement production, deforestation as well as the burning of fossil fuels like coal, oil and natural gas.

Explanation:

3 0

2 years ago

Battery acid has a density of 1.285 g/mL and contains 38.0% sulfuric acid by mass. The car battery contains 1.45 L of battery ac

larisa86 [58]

Answer: 708.2 grams

Explanation:

Molarity of a solution is defined as the number of moles of solute dissolved per Liter of the solution.

Given : 38 g of $H_2SO_4$ is dissolved in 100 g of solution.