Question

1. fórmula 1 punto a gas has a pressure of 710.9 mm hg at 12.3 °c. what is the temperature, in °c, at a pressure of 655.2 mmhg? round your answer to 1 decimal place. respuesta 19. elección múltiple 1 punto which of these contains only 1 type of molecule? element homogeneous mixture compound heterogeneous mixture 20. elección múltiple 1 punto which of these settles into layers? suspension element solution colloid

Explanation:

18.

Step1: Assume gas follows ideal - gas law and use Gay - Lussac's law

Gay - Lussac's law is $\frac{P_1}{T_1}=\frac{P_2}{T_2}$, where $P_1 = 710.9$ mmHg, $T_1=(12.3 + 273.15)$ K, and $P_2 = 655.2$ mmHg. First, convert the initial temperature to Kelvin: $T_1=12.3+273.15 = 285.45$ K.

Step2: Rearrange Gay - Lussac's law to solve for $T_2$

$T_2=\frac{P_2T_1}{P_1}$. Substitute the values: $T_2=\frac{655.2\times285.45}{710.9}$.

Step3: Calculate $T_2$ in Kelvin

$T_2=\frac{655.2\times285.45}{710.9}=\frac{186027.84}{710.9}\approx261.7$ K.

Step4: Convert $T_2$ to Celsius

$T_{2(Celsius)}=T_2 - 273.15$. So $T_{2(Celsius)}=261.7 - 273.15=- 11.5$ °C.

An element consists of only one type of atom, and thus only one type of molecule (in the case of mono - atomic elements like noble gases or di - atomic elements like $H_2$, $O_2$ etc.). A compound has different types of atoms combined chemically. Homogeneous and heterogeneous mixtures contain multiple substances.

Suspensions are heterogeneous mixtures where the particles are large enough to settle out over time due to gravity, forming layers. Solutions are homogeneous mixtures at the molecular level and do not settle. Colloids have particles that are intermediate in size and do not settle easily.

Answer:

$-11.5$ °C

19.