When a runner participates in a marathon, they travel a distance of 26.2 miles. How many kilometers is

When does a spring tide take place? At the beginning of spring Only during the spring season Only after spring is over At any ti

Naddika [18.5K]

Answer:

At any time.

Explanation:

Because it occurs in a full and a new moon.

HOPE THIS HELPS!!

8 0

4 years ago

Read that From picture and tell me the answer please

Dafna11 [192]

Answer:

1g Hydrogen

Explanation:

<h3>Getting to the equation:</h3>

Calcium in water reacts vigorously to give a cloudy white Precipitate (compound) called Calcium hydroxide alongwith the evolution of Hydrogen gas.

$\boxed{ \mathsf{Ca + H_2O \rightarrow Ca(OH)_2 + H_2}}$

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<h3>Balancing the equation: </h3>

This reaction is not in it's balanced form! The number of atoms of Hydrogen on the left is 2 while that on the right is 4,I.e.,they're not equal.

Adding a 2 in front of H2O solves the problem by making the number of atoms of each element on both the sides equal.

$\mathsf{Ca +2 H_2O \rightarrow Ca(OH)_2 + H_2}$

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

<h3>Observations:</h3>

Looking into the equation more carefully, we see:

1 atom of Calcium reacts with 2 molecules of water to give 1 molecule of Calcium Hydroxide alongwith 1 molecule of Hydrogen gas.

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

<h3>Gram atomic and molecular masses </h3>

Mass of one atom of Calcium = it's gram atomic mass

= 40 g

Mass of one "molecule" of Hydrogen

= it's Gram molecular mass

= gram mass of one atom × number of atoms in one molecule

= 1 × 2

= 2 g

So,

according to our observation:

One atoms of Calcium gives one molecule of Hydrogen (during the particular reaction)

=> 40g of Calcium gives = 2g of Hydrogen

•°• 1 g of Calcium gives = $\frac{2}{40}$

= $\frac{1}{20}$ g Hydrogen

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<h3>Answer:</h3>

We're provided with 20g of Calcium,

=> 20g of Calcium gives = 20 × $\frac{1}{20}$ g H2

= 1 g H2

_______________

Hope this helps!

6 0

3 years ago

Please help me urgent!

loris [4]

It decreases in volume, as the energy is lost.

4 0

3 years ago

Enter your answer in the provided box.

telo118 [61]

Answer:

i really dont know i just need points bad sorry bud

8 0

3 years ago

What is the volume of 0.80 grams of O2 gas at STP?

frez [133]

Answer:

The volume of 0.80 grams of O2 is 0.56 L

Explanation:

Step 1 : Data given

Mass of O2 = 0.80 grams

Molar mass of O2 = 32 g/mol

STP = 1 mol, 1atm, 22.4 L

Step 2: Calculate moles of oxygen

Moles of O2 = Mass of O2 / molar mass of O2

Moles O2 = 0.80 grams / 32 g/mol

Moles O2 = 0.025 moles

Step 3: Calculate volume of O2

1 mol = 22.4 L of gas

0.025 moles = 0.025*22.4L = 0.56 L

The volume of 0.80 grams of O2 is 0.56 L

5 0

4 years ago

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