Hello!
A reaction where the products have less chemical potential energy than the reactants had originally is called an exothermic reaction. Although the scientist didn't observe light or sound, an observation that would support her prediction is the rise in temperature after the reaction has completed. Exothermic reactions release energy in the form of heat, and the temperature would rise in an exothermic reaction.
Have a nice day!
Answer:
number of moles of the compound 
53 mole
Explanation:
Given that:
The total energy liberated = - 2870 kJ ( here , the negative sign typical implies the release of energy due to the combustion reaction)
The equation of the reaction can be represented as:
The energy needed to synthesize 1 mole of compound X = - 54.1 kJ.mol
Thus;
The total energy = numbers of moles of compound × Energy needed to synthesize 1 mole of compound X
Making the numbers of moles of the compound the subject; we have;
numbers of moles of compound = 
number of moles of the compound = 53.04990 mole
number of moles of the compound 53 mole to two significant figure
Answer:
25.157 cm³
Explanation:
Data Given:
Mass of Sugar (m) = 40g
Density of sugar given in literature = 1.59 g/cm³
Volume of Sugar = ?
The formula will be used is
d = m/v ........................................... (1)
where
D is density
m is the mass
v is the volume
So
Rearrange the Equation (1)
d x v = m
v = m/ d ................................................ (2)
put the given values in Equation (2)
v = 40g / 1.59 g/cm³
v = 25.157 cm³
volume of 40 g of sugar = 25.157 cm³
Answer: metals, 88 , periodic table , luster , heat, electricity , thin, right, opposite , appearance , luster , malleable , ductile, opposite , shiny, moderately
Explanation:
Most of the elements in the periodic table are metals. Most of them are present on the left side of the periodic table. Elements to the far right of the periodic table are nonmetals. Elements which exhibit properties of both metals and nonmetals and are termed metalloids or semimetals.
Metals are defined as the elements which loose electrons to attain stable electronic configuration. They are hard ,malleable ( betaen to sheets) ,ductile ( drawn into wires) ,sonorous ( produce sound ) etc.
Non-metals are defined as the elements which gain electrons to attain stable electronic configuration. They are brittle and soft and are the poor conductors of heat and electricity.
Metalloids are defined as the elements which show properties of both metals and non-metals. Metalloids are typically semi-conductors, which means that they both insulate and conduct electricity.
