Answer:
When you are exercising, your muscles need extra oxygen—some three times as much as resting muscles. This need means that your heart starts pumping faster, which makes for a quicker pulse. Meanwhile, your lungs are also taking in more air, hence the harder breathing.
Explanation:
A reaction is exothermic if Δ<em>H</em> (or 
in some textbooks) is negative:
- H₂ + Br → 2 HBr, ΔH < 0.
- CH₄ + 2 O₂ → CO₂ + 2 H₂O, ΔH < 0.
A reaction is endothermic if Δ<em>H</em> is positive:
- 2 NH₃ → N₂ + 3 H₂, ΔH > 0.
- 2 HCl → H₂ + Cl₂ ΔH > 0.
<h3>Explanation</h3>
The enthalpy of a system is the sum of its internal energy. ΔH < 0 indicates that the reactants lose internal energy in the reaction. Energy conserves, and those internal energies must have converted to some other form of energy. They typically end up as thermal energy. The reaction will release heat since it is exothermic.
Similarly, ΔH > 0 indicates that the reactants gains internal energy in the reaction. Energy conserves. As a result, the reaction must have gained energy from its surroundings. The reaction will be endothermic since it absorbs heat.
Explanation:
La ciencia puede entenderse como una forma que el ser humano encontró para adquirir conocimientos a través de métodos científicos, tecnológicos y basados en estudios, pruebas e investigaciones y no basados en el pensamiento para explicar los fenómenos humanos, de la naturaleza y de la vida.
La ciencia tiene un rol impactante y transformador en la sociedad, todo el conocimiento adquirido por el hombre a través de la ciencia ha transformado para mejor la vida de las personas, generando mayor calidad de vida, salud, educación, sentido crítico, etc.
En el escenario pandémico que vive el mundo actualmente, la ciencia es fundamental, a través de sus estudios e investigaciones que han ayudado en el desarrollo de vacunas efectivas para inmunizar a los humanos contra el virus y salvar vidas.
Precise is the close proximity of repeated measurements. In order to be precise, you need two or more measurements.
Accurate is the close proximity to the real (or expected) measurement.
<u>For Example: </u>
You are at the grocery store buying watermelons. The sign says that the watermelons all weigh 2 lbs. You weigh 3 of them on the scale next to the watermelon display. Their weights are 1.77, 1.80, and 1.82.
→ The <u>scale is precise</u> because it weighs all 3 of them at nearly the same value.
→ The <u>scale is not accurate </u> because their weights are not close to the expected value of 2.0
You take one of the watermelons to the cashier. The scale at the checkout counter weighs it as 1.99. The scale at the checkout counter is accurate. You cannot determine the precision of the scale at the checkout counter because you have no other values to compare it to.
Answer: Precise CANNOT be determined by one measurement.
Accurate CAN be determined by one measurement.
