Context givin in picture

A very hot cube of copper metal (32.5 g) is submerged into 105.3 g of water at 15.4 0C and it reach a thermal equilibrium of 17.

zysi [14]

Answer:

The initial temperature of the metal is 84.149 °C.

Explanation:

The heat lost by the metal will be equivalent to the heat gain by the water.

- (msΔT)metal = (msΔT)water

-32.5 grams × 0.365 J/g°C × ΔT = 105.3 grams × 4.18 J/g °C × (17.3 -15.4)°C

-ΔT = 836.29/12.51 °C

-ΔT = 66.89 °C

-(T final - T initial) = 66.89 °C

T initial = 66.89 °C + T final

T initial = 66.89 °C + 17.3 °C

T initial = 84.149 °C.

7 0

3 years ago

a closed flask of air (0.250 L) contains 5.00 "puffs" of particles. The pressure probe on the flask reads 93 kPa. A student uses

Sergio039 [100]

Answer: New pressure inside the flask would be 148.8 kPa.

Explanation: The combined gas law equation is given by:

$PV=nRT$

As the flask is a closed flask, so the volume remains constant. Temperature is constant also.

So, the relation between pressure and number of moles becomes

$P=n\\or\\\frac{P}{n}=constant$

$\frac{P_1}{n_1}=\frac{P_2}{n_2}$

Initial conditions:

$P_1=93kPa\\n_1=5\text{ puffs}$

Final conditions: When additional 3 puffs of air is added

$P_2=?kPa\\n_2=8\text{ puffs}$

Putting the values, in above equation, we get

$\frac{93}{5}=\frac{P_2}{8}\\P_2=148.8kPa$

3 0

3 years ago

Consider the reaction 2CuCl2 + 4K - 2Cul + 4KCI + 12. If 4 moles of CuCl2 react with 4 moles of KI, what is the limiting reactan

Free_Kalibri [48]

Haha i’m trying to do the same one i’ll make sure if i find out how too to get back to you!

8 0

3 years ago

How many electrons will each element gain or lose in forming an ion?

Amanda [17]

It depends on the number of valence electrons required to make octet or duplet( in case of H). For example, Nitrogen(atomic number = 7) has electronic configuration(2,5) which means nitrogen has 5 valence electrons and requires 3 more electrons to complete its octet. After gaining 3 electrons from atoms of an element with less electronegativity than N, it forms nitride ion ( $N ^{-3}$ ). Hope this helps.

8 0

3 years ago

What is the mass number of an atom containing 35 protons and 45 neutrons?

vodka [1.7K]

Answer:

Explanation:

1. Weight = 35 P and 45 N = 80

2. Atom: 35P = 35 electrons

3. Bromine

4. It's a non metal. It's in column 17. It will gain 1 electron (normally).

5. Ion: 35 protons, 36 electrons

6. Charge: - 1 usually, but there are exceptions

7. Anions go to the Anode. The anode attracts minus charged elements.

8. In an uncharged state, element 36 would be next. That would be Krypton which is always uncharged. It is a noble gas.

6 0

3 years ago