Answer:
Discovery of neutron
Explanation:
Until 1932, the atom was believed to be composed of a positively charged nucleus surrounded by negatively charged electrons, after successful discovery of electron by J.J. Thompson and proton by Ernest Rutherford.
In 1932, James Chadwick bombarded beryllium atoms with alpha particles.
As Chadwick had previously seen in experiment conducted by Frédéric and Irène Joliot-Curie, they had bombarded a sample of beryllium with alpha radiation.
Chadwick repeated the experiment and observed an unknown radiation, this showed no deflection what-so-ever.
He repeated this experiment by bombarding other materials, like helium, nitrogen and lithium,
Finally, Chadwick found that this radiation was composed of particles with a neutral electrical charge and had approximate mass of a proton.
This particle was then known as the neutron.
It's very simple... if we remember value of Universal Gas Constant R and Ideal Gas Law, so...
Ideal Gas Law
pV = nRT, where:
p - pressure (in kPa),
V - volume (in L),
n - number of moles (in mol),
R - universal cas constant (in kPa * L / mo l* K),
T - temperature (in K)
n = m/M, where:
n - number of moles,
m - mass (in grams),
M - molar mass of ingredient (in g/mol) - you find this at Periodic Table.
pV = nRT ---> pV = mRT/M ---> pVM = mRT ---> pVM/RT = m
p = 17615 kPa
T = 273.15 + 23 = 296.15 K
V = 43.8 L
R = 8.314 kPa * L / mol * K
M (for argon) = 39.948 g/mol
and
m = (17615 kPa * 48.3 L * 39.948 g/mol) / (296.15 K * 8.314 kPa * L / mol * K)
m = 13803.93 grams of Argon
The correct answer is option C, that is, carbon monoxide.
A combustion reaction takes place when a component reacts with oxygen and produces a huge amount of energy in the form of heat and light. A combustion reaction always exhibits oxygen as one reactant. The second reactant is always a hydrocarbon, that is, a compound formed of hydrogen and carbon. A combustion reaction always generates water and carbon dioxide.
Answer:
Explanation:
People who use marble to carve monuments and sculptures are always concerned because it can easily chemically weather.
Marble is a metamorphic rock derieved from limestone. The minerals that makes up limestone are calcite and dolomite. When a metamorphic transformation occurs, the rock is subjected to intense temperature and pressure. Marble is made of calcite and dolomite minerals.
Rain water dissolves carbon dioxide to form weak carbonic acid. This weak carbonic acid can easily dissolve marble thereby defacing the monument and the sculpture.
<span>When a chemist mixes oxygen gas and hydrogen gas to form
water, which is composed of one oxygen and two hydrogen atoms per molecule. The hydrogen and oxygen atoms bounds together by making a bond called covalent bond.<span> In a covalent bond, two atoms are bound
together because they each want to "share" each other's electrons.</span></span>