Which of the following have the greasiest ionization energy Bi, As, K or Ga?

Type your answer in decimal form. Do not round. 2/5 tons = pounds

jeka57 [31]

one US ton is 2000 lbs, thus 2/5 of that is just their product.

answer: 800 lbs

4 0

3 years ago

This reaction is sometimes used to inflate life rafts, weather balloons, and the like, where a simple, compact means of generati

tia_tia [17]

Answer: 10.2 grams

Explanation:

The balanced chemical reaction is :

$CaH_2(s)+2H_2O(l)\rightarrow Ca(OH)_2(aq)+2H_2(g)$

According to the ideal gas equation:

$PV=nRT$

P = Pressure of the gas = 740 torr = 0.97 atm (760torr=1atm)

V= Volume of the gas = 12.0 L

T= Temperature of the gas = 19°C = 292 K $0^0C=273K$

R= Gas constant = 0.0821 atmL/K mol

n= moles of gas

$n=\frac{PV}{RT}=\frac{0.97\times 12.0}{0.0821\times 292}$

$n=0.48$

According to stoichiometry:

2 moles of hydrogen are generated by = 1 mole of $CaH_2$

Thus 0.48 moles of hydrogen are generated by = $\frac{1}{2}\times 0.48=0.24$ moles of $CaH_2$

Mass of $CaH_2=moles\times {\text {Molar mass}}=0.24mol\times 42g/mol=10.2g$

Thus 10.2 grams of $CaH_2$ are needed to generate 12.0 L of hydrogen gas if the pressure of hydrogen is 740. torr at 19°C

5 0

3 years ago

What is the difference between atomic mass, relative atomic mass and average atomic mass

vesna_86 [32]

$\bold{\huge{\underline{\purple{ Answer }}}}$

Difference between Atomic mass, relative atomic mass and average atomic mass :-

<h3>Atomic Mass :-</h3>

Atomic mass is the mass of neutrons and protons present in the nucleus of an atom .
It is always calculated for a single element and having direct value
For isotopes also, the atomic mass is calculated separately . Example :- Carbon 12 , carbon 13 and carbon 14 have different atomic mass. 
The SI unit of Atomic mass is " u" and "amu"

<h3>Relative Atomic mass :-</h3>

Relative atomic mass is mean mass of the atoms of an element which is compared to the 1/12th mass of carbon - 12 .
Carbon - 12 is taken as a relative when we calculate the relative atomic mass of any element
For calculating relative atomic mass, we need to know the masses, percentage and abundance of all types of elements
Relative atomic mass is a dimension less quantity

<h3>Average Atomic Mass :-</h3>

Average atomic mass is the average mass of an atoms of a particular element by considering it's isotopes
While we calculate average atomic mass is a standardized number. Whereas, Average atomic mass sometimes varies geologically .
It also includes percentage, abundance and masses of given element .
In average atomic mass, We do not compare mean value with the 1/12 mass of carbon - 12
The unit of Average atomic mass is "Amu" or " u " .

5 0

2 years ago

Hydrogen cyanide, HCN, can be made by a two-step process. First, ammonia reacts with O2 to give nitric oxide, NO.

stealth61 [152]

Answer:

The mass of HCN is 79.65 g.

The mass of reactant which remain at the end of both reactions is 88.5 g.

Explanation:

Given that,

Mass of ammonia = 50.2 g

Mass of methane = 48.4 g

Hydrogen cyanide, HCN, can be made by a two-step process