All categories

3 years ago

I’m so confused on this one!

Chemistry

1 answer:

stellarik [79]3 years ago

5 0

The correct answer is 1) Ag, Si, I₂

Ag or silver is a metal. Silver is a transition element which lies in the d-block of the periodic table.

Si or silicon is a metalloid. Silicon is a metalloid which lies in the p-block of the periodic table.

I₂ or iodine is a nonmetal. Iodine is a halogen which lies in group 17 of the periodic table. All halogens are nonmetals.

You might be interested in

Three kilograms of steam is contained in a horizontal, frictionless piston and the cylinder is heated at a constant pressure of

lakkis [162]

Answer:

Final temperature: 659.8ºC

Expansion work: 3*75=225 kJ

Internal energy change: 275 kJ

Explanation:

First, considering both initial and final states, write the energy balance:

$U_{2}-U_{1}=Q-W$

Q is the only variable known. To determine the work, it is possible to consider the reversible process; the work done on a expansion reversible process may be calculated as:

$dw=Pdv$

The pressure is constant, so: $w=P(v_{2}-v_{1} )=0.5*100*1.5=75\frac{kJ}{kg}$ (There is a multiplication by 100 due to the conversion of bar to kPa)

So, the internal energy change may be calculated from the energy balance (don't forget to multiply by the mass):

$U_{2}-U_{1}=500-(3*75)=275kJ$

On the other hand, due to the low pressure the ideal gas law may be appropriate. The ideal gas law is written for both states:

$P_{1}V_{1}=nRT_{1}$

$P_{2}V_{2}=nRT_{2}\\V_{2}=2.5V_{1}\\P_{2}=P_{1}\\2.5P_{1}V_{1}=nRT_{2}$

Subtracting the first from the second:

$1.5P_{1}V_{1}=nR(T_{2}-T_{1})$

Isolating $T_{2}$ :

$T_{2}=T_{1}+\frac{1.5P_{1}V_{1}}{nR}$

Assuming that it is water steam, n=0.1666 kmol

$V_{1}=\frac{nRT_{1}}{P_{1}}=\frac{8.314*0.1666*373.15}{500} =1.034m^{3}$

$T_{2}=100+\frac{1.5*500*1.034}{0.1666*8.314}=659.76$ ºC

7 0

3 years ago

An intertidal area is one where the ocean meets the land.

Nikolay [14]

Answer:

T or True

Explanation:

The intertidal zone is any place or area where the ocean meets land, also known as shorelines or coastlines. The ecosystems found in these area experience lots of changes. Just think, whenever the tides are low, the area is exposed to air and the sun, but during low tide, it is submerged underwater.

8 0

3 years ago

Read 2 more answers

Which statement describes an electron?

GarryVolchara [31]

what are the options?

8 0

4 years ago

Read 3 more answers

Why should scientists perform experiments?

tia_tia [17]

Scientists observe the world around them, from which to draw questions. Their predictions as to the answer are what we call a “hypothesis”. Thus, a scientist’s job is to answer the very hypotheses that they and their piers come up with.

7 0

3 years ago

Read 2 more answers

1. If temperature is increased, the number of<br> collisions per second do what

GaryK [48]

Increase..................

7 0

4 years ago