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2 years ago

How many naturally occurring elements are there

Chemistry

1 answer:

arlik [135]2 years ago

4 0

Answer: Out of 118 elements, 94 occur naturally

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How many gallons in 2 L bottle

zepelin [54]

0.528 us liquid gallon

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2 years ago

Covalent bonding is the ____ of electrons

taurus [48]

Answer: sharing

Reason: They do this to gain stability. The reason they don’t actually transfer is because the difference in electronegativity values are above a certain value.

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2 years ago

What percent is tungsten made of from soil?

mars1129 [50]

I think i found your answers

4 0

2 years ago

How much energy is required to heat 36.0 g H2O from a liquid at 65°C to a gas at 115°C? The following physical data may be usefu

In-s [12.5K]

Answer:

energy required=qnet=87.75kJ

Explanation:

we will do it in three seperate step and then add up those value.

first step is to heat the sample of water upto 100C i.e upto boiling pont. because just after this sample of water started vaporization.

q 1= m c (T2-T1)

q1 = 36.0 g (4.18 J/gC) (100 - 65 C)

q1 = 5267 J =5.267kJ

next is to vaporize the sample at 100C

q2 = 36.0 g / 18.0 g/mol X 40.7 kJ/mol

q2= 81.4 kJ

Finally, heat the steam upto 115C

q3 = m c (T2-T1)

q 3= 36.0 g (2.01 J/gC)(115-100C)

q3 = 1085 J =1.085kJ

qnet=q1 +q2 +q3

energy required=qnet=87.75kJ

8 0

3 years ago

To answer this question, you will need to write the balanced equation and set up a BCA table. Using appropriate rounding rules,

Elenna [48]

Water decomposes when electrolyzed to produce hydrogen and oxygen gas. If 2.5 grams of water were decomposed 1.04 grams of oxygen will be formed.

BCA table:

2 $H_{2}$ O ⇒ $H_{2}$ + $O_{2}$

B 0.13 0 + 0

C -0.13 0.065 + 0.065

A 0 0.065

Explanation:

Balanced equation for water decomposition into hydrogen and oxygen gases

2 $H_{2}$ O ⇒ $H_{2}$ + $O_{2}$

B 0.13 0 + 0

C -0.13 0.065 + 0.065

A 0 0.065

Number of moles of water = $\frac{mass}{atomic mass of 1 mole}$

mass = 2.5 grams

atomic mass= 18 grams

number of moles can be known by putting the values in the formula,

n = $\frac{2.5}{18}$

= 0.13 moles

2 moles of water gives one mole of oxygen on decomposition

so, 0.13 moles of water will give x moles of oxygen on decompsition

$\frac{1}{2}$ = $\frac{x}{0.13}$

x = 0.065 moles of oxygen will be formed.

moles to gram will be calculated as

mass =number of moles x atomic mass

= 0.065 x 16

= 1.04 grams of oxygen.

7 0

3 years ago