Find the amount of heat (Q) needed to raise the temperature of 5.00 g of a substance from 20.0 C to 30.0C if

The atomic number of fluorine is 9. How many electrons does an ion of fluorine have if it is represented by the symbol shown bel

Irina-Kira [14]

See charge on ion is -1 .

Hence it has taken 1 electron

Now first look at EC of Fluorine(F)

$\\ \bull\sf\dashrightarrow 1s^22s^22p^5$

Now one electron added .hence no of electrons is 10now

Look at the EC

$\\ \bull\sf\dashrightarrow 1s^22s^22p^6$

Or

$\\ \bull\sf\dashrightarrow [He]$

Option C is correct.

5 0

3 years ago

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PLS HELP ASAP!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

xz_007 [3.2K]

Answer:

The answer is (D).

Explanation:

A(n) "electromagnet" is an electric circuit that produces a magnetic field.

6 0

3 years ago

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What can a drop of liquid mercury be described as?

Tomtit [17]

A drop of iquid mercury is D. <span> a pure substance and an element. This is because mercury is an element which exists as liquid in the normal or standard conditions. It is a metal that is toxic to all environments. It is pure because it is composed only of one kind of substance.</span>

8 0

4 years ago

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What is the change in enthalpy when 4.00 mol of sulfur trioxide decomposes to sulfur dioxide and oxygen gas? 250 2(g) + O2(g) ®

lidiya [134]

Answer: A. -396 kJ

Explanation:

The standard enthalpy of formation or standard heat of formation of a compound is the change of enthalpy during the formation of 1 mole of the substance from its constituent elements, with all substances in their standard states.

$2SO_2(g)+O_2 (g)\rightarrow 2SO_3(g)$ $\Delta H^0=198kJ$