1) Chemical equation
<span>2NH4Cl(s)+Ba(OH)2⋅8H2O(s)→2NH3(aq)+BaCl2(aq)+10H2O(l)
2) Stoichiometric ratios
2 mol NH4Cl(s) : 54.8 KJ
3) Convert 24.7 g of NH4Cl into number of moles, using the molar mass
molar mass of NH4Cl = 14 g/mol + 4*1 g/mol + 35.5 g/mol = 53.5 g/mol
number of moles = mass in grams / molar mass
number of moles = 24.7 g / 53.5 g/mol = 0.462 moles
4) Use proportions:
2 moles NH4Cl / 54.8 kJ = 0.462 moles / x
=> x = 0.462 moles * 54.8 kJ / 2 moles = 12.7 kJ
Answer: 12.7 kJ
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There is no problem with the model formed by atoms as solid spheres for macroscopic measurements because the atoms are extremely small.
<h3>What is Dalton's atomic model?</h3>
This was formulated in 1808 and states that atoms with spheres cannot be divided. It also states that solids are formed by contact between the spheres and chemical compounds from joining of atoms of two or more elements.
The size of the atoms in the form of sphere is very small as it is known that it is of the order of 10⁻⁹ m, therefore, having a macroscopic crystal more than 10⁻⁶ m in length which is why the model of the atom as solid spheres for macroscopic measurements has no problem.
Read more about Dalton's atomic theory here brainly.com/question/13157325
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Answer:
A forensic palynologist is a spore and pollen expert that helps solve crimes.
The case that Mildenhall worked on was about a murder that involved a prostitute. The police couldn’t find a trace to help solve the case, so they called Mildenhall to help with pollen clues. He was able to find trace evidence in the pollen, which helped police connect the victim to a gang hangout by the crime scene.
A forensic palynologist can help with a criminal investigation by comparing pollen from the suspect and the victim using a comparison microscope to determine if the pollen matches.
The challenges of using a forensic palynologist in a criminal investigation are that judges and juries may have a hard time understanding palynologists.
Explanation:
Answer:
<h3>If the substance has high melting/boiling point, if it requires high temperature to dissociate into simpler particles, if it's structure is hard and if it conducts heat and electricity quite frequently, then it would be "Ionic compound" otherwise, it will be covalent compound.</h3>
Answer: Fe(OH)2
Explanation: Fe has a charge of 2+ and OH has a charge of 1-. Switch the charges of the two elements to get the formula of Fe(OH)2.