Answer:
1. Lanthanum-139 atom is the stable isotope of lanthanum with relative atomic mass 138.906348, 99.9 atom percent natural abundance and nuclear spin 7/2.
2. In fact, over 80% of electric cars sold globally utilized permanent magnet-based motors in 2019. These magnets are typically made with rare-earth materials such as neodymium and dysprosium, which have a very geographically constrained supply chain.
3. It is the second most reactive of the rare-earth metals after europium. Lanthanum oxidizes in air at room temperature to form La2O3. It slowly reacts with water and quickly dissolves in diluted acids, except hydrofluoric acid (HF) because of formation of a protective fluoride (LaF3) layer on the surface of the metal.
Explanation:
Fossils are the preserved remains or traces of animals, plants, and other organisms from the past.
Fossils are important evidence for evolution because they show that life on earth was once different from life found on earth today.
Usually only a portion of an organism is preserved as a fossil, such as body fossils (bones and exoskeletons ), trace fossils (feces and footprints), and chemofossils (biochemical signals).
Paleontologists can determine the age of fossils using methods like radiometric dating and categorize them to determine the evolutionary relationships between organisms.
Like in general, or is there something u didn't put?<span />
<h2>Answer:</h2>
Scientific questions are question which are solved involving experiments, observations, or surveys.
Like, Is cancer caused by uncontrolled cell division.
<h3>Explanation:</h3>
Scientific questions are always testable questions. They can be solved by using scientific techniques like PCR, titration etc.
Here the given question in the example can be tested, by making the observations of the cell division of the cancer patients. Then by inducing uncontrolled cell division into normal cells to look for the effect of cell division on cancer.
The questions like, "is sadness can be controlled by talking?" is not a scientific question.
Respuesta:
2 m
Explicación:
Paso 1: Información provista
- Volumen inicial (V₁): 100 mL
- Concentración inicial (C₁): 4 m
- Volumen final (V₂): 200 mL
- Concentración final (C₂): ?
Paso 2: Calcular la concentración de la solución final
Queremos perparar una concentración diluida a partir de una concentrada. Podemos calcular la concentración de la solución diluida usando la regla de dilución.
C₁ × V₁ = C₂ × V₂
C₂ = C₁ × V₁ / V₂
C₂ = 4 m × 100 mL / 200 mL = 2 m
