Phenolphthalein is an acid indicator, which means when we add water (pH 7) to it, it ionizes giving a pink color. We all know acid gives in solution. When we add phenolphthalein to acid due to the common ion effect concentration increases. turned the solution pink.

Explanation:

5 0

2 years ago

How many kilograms of oseltamivir would be needed to treat all the people in a city with a population of 400000 people if each p

madam [21]

Answer:

300 kg

Explanation:

The number of people in the city, p = 400,000

The number of capsules of oseltamivir each person consumes per day, n = 2 capsules

The number of days each person consumes the oseltamivir capsules, t = 5 days

The mass of oseltamivir in each capsule, m = 75 mg

The mass of oseltamivir needed to treat all the people in the city, <em>M</em>, is given as follows;

M = n·t·m·p

∴ M (in milligrams) = (2 × 5 × 75 × 400,000) mg = 300,000,000 mg

1,000,000 mg = 1 kg

∴ 300,000,000 mg = 300 kg

The mass of oseltamivir needed to treat all the people in the city, <em>M</em> = 300 kg

3 0

3 years ago

It takes 2,267 joules of heat to raise the temperature of a 44.5 gram sample of a metal from 33.9°C to 288.3°C. What is the heat

ehidna [41]

Answer:

$\boxed{\text{0.200 J$^{\circ}$C$^{-1}$g$^{-1}$}}}$

Explanation:

The formula for the amount heat q absorbed by a substance is

q = mcΔT

where

m = the mass of the substance

C = the specific heat capacity of the material

ΔT = the temperature change

Data:

q = 2267 J

m = 44.5 g

T₁ = 33.9 °C

T₂ = 288.3 °C

Calculations:

ΔT = (288.3 - 33.9) °C = 254.4 °C

$\begin{array}{rcl}2267 & = & 44.5 \times C \times 254.4\\2267 & = & 11 180C\\C& = & \dfrac{2267}{11180}\\\\& = & \textbf{0.200 J$^{\circ}$C$^{-1}$g$^{-1}$}\\\end{array}$

$\text{The specific heat capacity of the metal is \boxed{\textbf{0.200 J$^{\circ}$C$^{-1}$g$^{-1}$}}}$

5 0

3 years ago