Answer:According to the sliding filament theory, a muscle fiber contracts when myosin filaments pull actin filaments closer together and thus shorten sarcomeres within a fiber.
Explanation:
No need for an explanation if i just answered it
Answer: the molecular formula of the compound is still the same i.e CO2
Explanation:
Phosphoric acid has 3 pKa values (pKa1=2.1, pKa2=6.9, pKa3= 12.4) and after 3 ionization it gives 3 types of ions at different pKa values:
H₃PO₄(aq) + H₂O(l) ⇌ H₃O⁺(aq) + H₂PO₄⁻ (aq) pKₐ₁
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</span>H₂PO₄⁻(aq) + H₂O(l) ⇌ H₃O⁺(aq) + HPO₄²⁻ (aq) pKₐ₂
HPO₄²⁻(aq) + H₂O(l) ⇌ H₃O⁺(aq) + PO₄³⁻ (aq) pKₐ₃
The last equilibrium is associated with the highest pKa value (12.4) of phosphoric acid. There the last OH group will lose its hydrogen and hydrogen phosphate ion (HPO₄²⁻) turns into phosphate ion (PO₄³⁻).
Answer:
there are 20 oxygen atoms in 4.00 moles of Dinitrogen pentoxide
Explanation:
there are 2 atoms in an oxygen molecule , so each oxygen molecules has at least 2. Dinitrogen pentoxide is N2O5, which has 7 atoms, 2 nitrogen and 5 oxygen. 1 molecule of N2O5 has 5 oxygen atoms, so 4 of then would be 20
Answer:
The density of the metal sample is 2.70 
Explanation:
Density is a magnitude that allows you to measure the amount of mass in a given volume of a substance. Then, the expression for the calculation of density is the ratio between the mass of a body and the volume it occupies:

Density, according to the International System of Units, is usually expressed in kilograms per cubic meter (kg / m3) or gram per cubic centimeter (g / cm3). Although it can also be expressed in any other unit of mass by volume.
So, for the calculation of density you know that:
- mass of the sample= 10 grams
- volume of the sample = volume on the cylinder after immersion - volume on the cylinder before immersion= 38.7 mL - 35.0 ml = 3.7 mL
Then:

d=2.70 
<u><em>The density of the metal sample is 2.70 </em></u>
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