Answer:
Lead
Explanation:
The subatomic particles within an atom can be used to know the atom or element given.
Of particular interest is the number of protons within the atom.
The periodic table is based on the atomic number of atoms. This atomic number is the number of protons within an atomic space.
So; If we know the number of protons within an atom, we can know the element.
The number of protons given is 82, the element is therefore lead.
Answer:
E = 147000 J
Explanation:
Given that,
The mass of meteor, m = 50 kg
The altitude of the meteor, h = 300 m
We need to find the potential energy of the meteor. The formula for the potential energy is given by :

Put all the values,

So, the required potential energy is equal to 147000 J.
Answer:
HCO₂
Explanation:
From the information given:
The mass of the elements are:
Carbon C = 26.7 g; Hydrogen H = 2.24 g Oxygen O = 71.1 g
To determine the empirical formula;
First thing is to find the numbers of moles of each atom.
For Carbon:

For Hydrogen:

For Oxygen:

Now; we use the smallest no of moles to divide the respective moles from above.
For carbon:

For Hydrogen:

For Oxygen:

Thus, the empirical formula is HCO₂
the answer is b
The posterior pituitary secretes two important endocrine hormones—oxytocin and antidiuretic hormone
Hello!
As a chemical reaction occurs and the thermometer in the container records a decrease in temperature, the statement that is true about the reaction is: <span>The reaction is endothermic because heat was taken in by the reaction.
Endothermic reactions are those that require energy in the form of heat to be completed. Technically, in these reactions, the enthalpy of the products is higher than the enthalpy of the products. The requirement of energy causes the temperature to decrease. A general expression for an endothermic reaction can be written in the following way:
A + </span>Δ → B (Where Δ means heat)
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